I run crdroid (now on pixel but before that it was xiaomi). I suggest your check it out.
postmarketOS, Mobian.
Unfortunately these OS's don't even support the "phone" use for most hardware. They're probably fine if you just want to turn your old phone into a palmtop-class device, but not for much else.
It depends on the hardware a lot. Quite a few people use both of them for daily driving.