- Unlock bootloader (depending on vendor, you have to do an online verification),
- flash a recovery.img,
- load into recovery mode (which, depending on the phone, might need extra work)
- wipe some caches,
- select new os/rom image,
- pray it doesn’t brick your phone.
You’d think someone would’ve learned a thing or two from the easy graphical installations linux and even windows have been offering since the late 2000s.
I can’t answer your question, but is quite unfortunate. It really shortens the lifespan of many phones as they stop receiving OS and security updates after awhile (and in many cases, right away).
I don’t think most users care about that. I certainly use mine until they get slow and stop holding charge.
People I work with tend to get a new one when their provider pokes them to get a new phone, since way too many people think a phone contract should cost £50 a month and that the phone is somehow “free”.
Google should push third parties to a default build of Android that Google maintain, rather than having to update and maintain their own. Imagine if you had to go to Dell or Lenovo or ASUS for your Windows updates? The current Android ecosystem is nonsense.