It's not sudden, and it's about control. You probably don't remember a time when you could switch/remove batteries from your phone. All manufacturers removed this ability.

That was one very good reason for me to choose a FairPhone. (Almost?) everything is user replaceable. It has been in my pocket for a could of years and I have not needed to replace anything yet. But I do like having the option.

Samsungs Galaxy S21 is also really simple to fix stuff. The back is made of relatively flexible plastic connected via glue, which you can easily get under by blowing into the charging/speaker port. Once your inside its all just a lot of screws.

Had to reattach the battery ribbon cable after my phone fell one too many times (I could have also just fixed it by pressing on the back in the right place, but I only really figured that out after I disassembled the phone).

EU is bringing user replaceable batteries back. Starting 2027 all new consumer devices must have user replaceable batteries.

I have a Volla Phone running Ubuntu Touch. In order to insert my SIM and SD cards I had to take off the back cover (which is intended and I just had to pull on a small gap in a corner of the device) which also made it very obvious that it's easy to take out the battery should I have the need to swap it out.