Thanks to everyone who provided advice and links. I've uninstalled v10 from my Pixel 2 (yeah, I know it's a dinosaur) and installed the 8.x. For me, the worst thing about the "update" was the inability to work with encrypted notes, or to encrypt notes at all, on my phone. Inexcusable. I'm okay for now, but if they make it impossible to use this legacy version, I'll have to unsub and delete my account.
Anyone know of any good note services that do a good job with (phone-accessed) note encryption?