Android May Soon Restrict On-Device ADB, Affecting Shizuku, libadb and Developers
(kitsumed.github.io)
Sailfish is decent, but yes, tied to the company. Ubuntu Touch and Sailfish suffer from the same problem, limited app repositories, excluding waydroid, I mean linux software, but Ubuntu Touch at least has Libertine Containers with PPA support....
PostmartketOS, Mobian, PocketBlue all use mainline kernels, so that might limit your options, but have access to packaged and Flathub! (pmOS is still better for device comparability)
There are more options, niche as they may seem.... Like I was not aware of OpenSUSE mobile, NixOS for phones, were actually a thing. I had heard of Arch mobile, thanks to Arch ARM, but again, not a lot of documentation that I've seen
Also I'd check check out !linuxphones@lemmy.ca