This is also true of early smartphones. They were made to have easily replaceable batteries, and I assume you could buy those batteries too.

But that turned out to be irrelevant because of the replacement schedule. It seems clear that the frequency with which people replace their phones is what drove the decisions to make maintaining them difficult. If nobody ever needs to maintain the phone, why would you put any effort into helping them hypothetically do so?

The analog of Moore's Law for smartphones is already dying and there was a lot of news coverage a while ago of how people seem to be keeping their phones. That may drive the development of phones that can last longer than two years.

Something that every PocketPC user rapidly learned to be adept at because without the boosted Chinese batteries the thing didn't last that long. Amazing for the time, but looking back, what a primitive device. And you had to pay for OS upgrades!