Don’t take the reply of ApB too strongly. If you have used Debian for more than 15 years Sailfish might be a good option. Currently it is the best linux phone out there.
There are some drawbacks, Google apps or banking apps can be an issue sometimes. And some people have strange expectations, installing 10s of Android apps is like installing 10s of Windows apps under wine on a desktop
Edit: I would think the Xperia 10 II is the best currently supported. Also has Arm 64bit support, so will probably have the most longevity in it regarding support from Jolla. Oh, and the biggest battery.