I think 90% chance of apple going for the EU-Specific model just like they did for Digital markets act, 10 chance of screws, 0% chance of actually popping the back cover off with bare hands.
For Samsung, 50% chance EU-Specific models 40% chance screws, 10% chance back cover tool-less removal. (Edit: typo)
As for other smaller manufacturers, probably just 50%/50% either screws or tool-less back cover removal.
iPhones are already one of the best phones around in terms of battery replacement- maybe not for DIY, but for the fact that Apple will replace your battery for you themselves for a very reasonable price.
https://support.apple.com/iphone/repair/battery-replacement
An iPhone 13 Pro battery replacement, done officially through Apple, is USD$89. They will replace your battery on models all the way back to the iPhone SE or iPhone 6. At that price I can’t understand why anyone would go third party/diy.
Even the newest 16 Pro Max is only $119 for a brand new battery fully installed officially by Apple. If you’ve got apple care it’s “free”.
One thing to note is that Apple will only replace the battery if the phone turns on. If the battery stops taking a charge and won’t turn on, they’ll tell you to get a new phone.
If the phone doesn’t turn on then there’s something more than just the battery, and a new one won’t do any good.
While the phone not turning on can indicate other issues, sometimes it’s just the battery.
Thought it was dankpods, but it was his mechanic James:
https://youtu.be/IpT7h8VJX-0
It’s generally not just the battery though. A battery going completely dead in a recent mobile phone and not holding any charge whatsoever or even functioning is extremely rare.