It’s not like a battery is soldered there, you can still replace it and it’ll cost you much less than getting a new phone. AFAIK I can still get a new battery on my iPhone 7 which is 4.5 years old.
Replacing iPhone battery feels like reassembling a mechanical watch. It isn’t soldered, but it’s glued in weird way requiring applying heat. To change battery, you have to disconnect 4-5 tiniest connectors, looking like LPT for fleas, extremely fragile.
Changing the battery is an operation that you likely only do once in the phone's lifetime. It doesn't make sense to have design constraints just to make that operation super-quick.
Currently it takes an hour at most to do at any repair shop. It's good enough. What matters is that it's possible for a reasonable price.
Well yeah, I've replaced the battery and the button on my iPhone 4s myself back in the day. Handling those tiny connectors feels like you're performing an open heart surgery if you're not doing it for a living. But let's be honest, personal computing devices are going to get smaller and more intricate in the next decades. The days of replacing the battery yourself are long gone.
