Thanks gents! I had it charging on a table and noticed walking by that the screen was illuminated (which was odd.) Later that day when I went to use it, it was completely dead. I read all of the tips, holding down buttons, etc.; no matter what I couldn't get it to turn on. Called Apple support, they had me plug it into a PC, no communication. Took it to the Apple store, they couldn't rescusitate it and pronounced it dead. My guess is that while charging the battery developed a "whisker"; basically a short-circuit.

I researched repair and battery replacement. Apparently it's very difficult to open the case and the battery was not designed to be removable, someone characterized the difficulty as 7 out of 10. One site suggested that a professional repair would cost more than $500, which is a lot to invest in a device that was already 7 years old. So I bought a new (gently used) one for $875. If it lasts me another 7 years, that's better than lugging around a lot of books and making mistakes while I fumble to turn pages. Plus I use the iPad for other hobbies, and it serves as backup to my laptop.

For what I do, I definitely didn't need the speed of the new M2 processor. It bothered me to put it in the trash, but like so many things today, they just aren't designed to be repaired or maintained long-term.