Not sure I understand why. I’m using Calibre version 5.42 with the following plugins installed
KFX Input 1.48.0 by jhowell
KFX output 1.58.0
DeDRM 7.1.0 by Apprentice Alf
Obok DeDRM 7.1.0
on both my macs running Catalina.
The source code is available on GitHub and it has decent plug-in support and a pretty active group of developers.
Despite mostly being proprietary I would use a dedicated app., as you are exploring already. Bookends is my choice, I think there are even cheaper or free ones, Zotero? And the more complicated to set up but open source LaTeX bibliography, which can produce a kind of plain text version of any reference. Every bibliography app I know of lets you group and sort in all kinds of useful ways.
I don’t want to pile in on Amazon but I just found a book I needed, an academic one, not cheap, on Kindle is just gooooorrrrn. 
There is a set of issues here which would take us into politics and off topic… I wouldn’t want too much under their direct and fiat control.
I have some other systems for finding references I have made in DEVONthink 3. Does anybody know a way to make Bookends searchable in Finder by the way?
I have dozens of references in hard copy in my planner and notebooks, a system I used since my twenties: I have an idea of time scale from where something is in the notebook. I actually read maybe 1% of what I have noted over the years, even then not often the whole book or paper.
The small number of books you need to keep track of should work ok in a notebook I would have thought? By the way the ‘citation industry’ is totally out of control and ridiculous now especially in the sciences.
I’ve tried it out quite a few time before it stuck. I takes some time to set up to your liking and you really have to enjoy tinkering with this kind of stuff if you want to enjoy Obsidian to its fullest.
It does hurt a little when I look at native apps like DevonThink or Bear, but the possibilities of Obsidian are just so much bigger than any other (native) app.
One of my favorite uses is a ‘What to do’ dashboard. It shows me stuff like books/shows/comics I’m currently reading or watching. But it also suggests random movie/shows/books from my ‘someday’ list. And it shows three random topics that I started exploring that I may be interested in continuing. Now whenever I have some free time in which I don’t know what to do, I can just check out my dashboard and continue with wathever appeals to me.
I use Reminders for stuff I want to watch with my wife, so movies and TV series. I use tags for the channel, e.g. Netflix, Amazon Prime, etc. so if we’re in a situation where we’ve only got access to a couple of channels we can easily filter when picking something to watch. I also keep things in there that I want to purchase or download, or films we want to see at the cinema, again with the tag cinema or purchase. When it’s something with a forthcoming release date, I often put the release date into the date field so it comes up as an actual reminder. So I imagine this would work brilliantly for books, too!
I have used a system on DEVONthink 3. I touched on it in another comment. I found it pretty easy to incorporate bibliographies into my notes system there.
I use(d) a Keyboard Maestro snippet to expand a short cut to this more or less in the title of the note that i call up with a keyboard shortcut too.
" note bibo 2022-05-13"
then enter either manually or by copy and paste the book details etc., so you can sort in all kinds of ways quite easily. As you say, you can add tags for various aspects you need.
I am however returning probably to a dedicated Bibliolgraphy app. I use one anyway but mostly to formatt citations.
I also take screen shots of podcast info pages and of books on Amazon and publishers pages and keep them in photos; I have quite a few and a better use of the photos app than endless inane shots of family dogs and another few hundred meaningless vacation shots. In fact I use photos as a kind of note taker really. Thanks for bringing my mind to focus on my own real use of things by your interesting question! 
I use Libib to manage my library of specific-topic books. It’s mostly filled with books I own because I often buy at used book stores and estate sales and want to avoid purchasing the same book twice, but I do have “to read” and “to purchase” tags. I also needed something that I could quickly access “in the field”, so that ruled out a lot of things.
It’s built for library management, so it has nice features like scanning barcodes, automatically pulling in covers (and other info) from online sources, etc. And perhaps more relevant to the OP, importing from CSV (assuming GoodReads lets you export, of course!).
Their Basic plan is free and designed for home/personal libraries. The paid Pro account has features for much larger libraries, and lending. Over the years I’ve donated a few times just to keep the service going, since a Pro account offers far more than I need ($100/year).
I think the key for a “to read” list is the ease of getting recommendations into it — and then ease of use. I don’t think Libib would work well for my general reading lists because my recommendations come from all over the place and I don’t want to spend time inputting data. (Scanning barcodes, on the other hand, is trivially easy.) So right now I’ve got a folder of screenshots that is generated by automatically filing anything in my Downloads folder whose name contains “book rec” and a single note in the Notes app. Quick and dirty entry, but not easy to use!
Well I just had a productive couple of hours cackling like Mr Burns and importing DRM-free copies of all my digital books to Calibre. Thank you so much for sharing this idea with me!
I haven’t made a decision on my To Be Read list management yet, but this was a very exciting detour!
Create a TBR tag in Calibre
FWIW My original to be read list was a plain text file in DEVONThink. I’m deciding how to move it into Obsidian. I want to see if I can get a bit more so I;m looking at linkages between Obsidian and Bookpedia or even considering moving books into Zotero wher ethe links to Obsidian are much easier to do.
What I think my ideal would be is a note for every book, that tracks my notes and annotations, has all the bibliographic data in it and also allows me to see when I started and finished reading it on every instance of reading and re-reading. And if I re-read book the new notes and annotations add on to the existing book note. Problem is with over 3500 books so far in the library, about half e-books and half paper books I need an automated way to create the individual books notes from my existing Bookpedia database. Still not clean way to do that I can see yet. But I’m documenting ideas and playing with several tools.
Check out my comment here: How to track books to read - #28 by jeroen
If BookPedia has a way to export to csv or json, you can use the import-plugin I mention in the fourth step. My Goodreads library was notably smaller than yours (about 300 books), but after a bit of tinkering with the csv it worked like a charm, including stuff like tags and read dates.
This is the result of the import:
Overview page:
Details:
Most my books are paper so that bit doesn’t work unfortunately. I only have about 200 digital books. My TBR (To Be Read) list is over 1000 books, most of which I do not own (YET).
After pondering Calibre a bit I have put my Calibre folder in iCloud, and then I have indexed it in a new database in DevonThink called Bookshelf. This gives me 3 ways to access the books - via Calibre’s interface, via Files on any Mac device, or through DevonThink. That way I can leverage DT’s search functions, keep the functionality of Calibre “on top” and I can rummage in a dedicated folder if I fancy.
For those wondering, Calibre files all books in one folder locally (default name Calibre Library - you can choose folder location). All titles are in their own subfolder named after the author (sorts by first name).
As a result of this flurry of book activity I have taken a second detour and started removing my PDF books from GoodNotes (filed there mostly for lack of a better place to put them). Sorting my GoodNotes into only my own notebooks was also a pending task, so it’s nice to have sorted a big step in this puzzle too! (I don’t see GoodNotes mentioned much in here, but it is a superb notebook app, and if you enable backups you can keep PDF copies of your notebooks locally.)
Anyway, none of this has solved my TBR list management, but it feels like a huge leap forward in terms of streamlining my processes. I move ever closer to tech set-up nirvana 
Genius! I had no idea that was there. Diolch yn fawr.
Nope, but it is an SQLIte Database So I can potentially write my own query to extract everything and perhaps even format it as markdown appropriately.
+1 for BookTrack. It has nice support for widgets, too, and works great on Mac, iPad, and iPhone!
I just started using the app BookBuddy for all the physical books I own. I really like it but it is time consuming if you have the patience.
I thought some may be interested to know what I went with in the end. I’ve moved to LibraryThing.
I chose it because it has a robust privacy policy and seemed very familiar to GoodReads, and I decided I didn’t want to have too much of a difference in interface (I’m leaving GoodReads because of who they’re owned by, not because of their service).
I only want to track my TBR list (I already track books I’ve read on a spreadsheet) so I tweaked my GoodReads export, and only imported to LibraryThing my To Read shelf (this is very easy to do, in your spreadsheet app of choice just filter the shelf you’re interested in, then copy and paste in a new csv file). LibraryThing does have ‘Currently reading’ and ‘Read’ shelves if you like that on GoodReads. It also has an iOS app but I’ve not tried that yet.
Thank you all for your help with this 
The iOS app is really useful in terms of entering books; the camera of an Android or iOS phone scans the ISBN bar code, and LibraryThing sucks up the metadata.
I’m currently using Bookends, but I want to simplify my setup. There are good suggestions here. The contenders at the moment are LibraryThing and Libbib. They both have ISBN scanners, which are really useful. However, bulk editing seems a bit clunky on both.
In the lastest Macmost, Gary suggested using Numbers. I admit, it never crossed my mind. I’ll share it, for those who are looking for a simple solution.
I use the Numbers app for situations where I want to do arithmetic with some of the fields – like my Checkbook and Expenses spreadsheets.
For text and image oriented tables, like keeping track of my books, I use the Notenik app.
