As other users on the thread I also needed to change phone recently (the old one was already 5 years old and was begging for a replacement).
I wanted an Android with a headphones Jack connector, and a "you can reach all the screen comfortably with you thumb while using one hand" size, nothing else (not even camera, I simply don't use it other than the occasional qr reading).
All "good" results are from even more than 5 year old phones and obsolete versions, and no sign to change unfortunately.
In the end I simply searched for the narrowest possible, and ended with the Xperia 10 III. 68mm wide, Android 11 from 2021, and decently fast. It's looong however (21:9 screen) but very usable with one hand because you can grab it without issue.