There is. Fairphone advertises this feature. Here’s the guide (note: non of thisis possible without accepting to enter into agreement with Google): Bootloader Unlocking Code for Fairphone - Fairphone
The physician case seems a bit extreme and silly. Wanting to leaving privacy-invasive advertising companies out of my phone sounds a lot more reasonable, IMHO.
I don’t see this as an alternative really: I’m fairly certain I’d have the EXACT same experience if I went to OnePlus. The big difference is that FairPhone pretends to be an alternative, but the produce I received is the exact opposite of how they present themselves.