Ability for OS makers to freely port their systems would be super cool. Replacable batteries with this and imagine how used phone market would shine up.
My parents won’t spend more than 150$ on a phone. I don’t want to buy them cheap Android phones that are always loaded with spyware and installs dozens of bloat on first boot. I want to buy used 5 year’s old phone with much high build quality, then slap new lightweight OS and new battery in it.