Well THAT’S a bummer!! According to this, I can’t format a external hard drive from iPad OS, nor can I use my old fat or ntfs drives. 
He is using a beta version, so it might be different with the release version. I tried with my iPhone on the release version of iOS 13 and I could read/write files to an old MS DOS formatted USB stick. When I plugged it in my Mac, Disk Utility said it was a FAT-16 drive.
Thanks for this, will be sure to give it a watch when I take the plunge on updating.
I’m still waiting too.
I would expect FAT16 and FAT32 support (exFAT is mentioned as supported in the video too), but not NTFS. Even on the Mac, NTFS requires a custom and licensed driver, right? I’m running Paragon for this. Of course, I’d love to see NTFS support due to how it handles large volumes…