If I were not paying for the pro version of Yahoomail I’d probably be a Fastmail user. I also have an old Hotmail account - which I now log into at outlook.com - and it’s not bad. I have a gmail account, but … I don’t trust Gmail. (I don’t trust Yahoo either, but at least I don’t see ads with them.)
I’m grandfathered in at $20/yr, which I’ve paid since 2001, I think, but the regular pricing today is $35/yr. Gets you no ads, several light/darkthemes, a clean, fast interface, folders (I prefer those to tags), multiple alias addresses that can be added/deleted at will, the ability to use any email addresses from domains you own, offers something like 1Tb storage, and increased attachment size (I think free accounts have a 25Mb limit for any individual email, I don’t remember what the limit is on my Pro account). Last year(?) they added a Photos and Documents view that lets you see all of the attachments you’ve ever sent or received, be it a photo or a document, and it’ll label them appropriately. You can even preview these attachments in a side-by-side view.
I’d also give a shout-out to the Yahoomail iOS app, which is actually well designed and stable; I use it to incorporate my mail from my non-Yahoo mail accounts when I’m mobile.