first results on a quick search for phones that allow bootloader unlocking.

Hopefully, all of the devs, (or at the very least, most of the them) move over to help speed up and improve the alternative OS's

It would be a beautiful kick in the face to Google if there a relatively quick mass migration from Android to any or all of those.

https://www.howtogeek.com/buy-these-brands-if-you-truly-want-to-own-your-phone/