Debian! It’s stable, elegant, and doesn’t impede customization. I distro-hopped a lot over the years - some that I ended up disliking included KaOS (severely limited software repository), Clear Linux (only way to get ffmpeg was to compile it from source) and Fedora (very slow); most I liked, and just decided to move on at some point. But I kept coming back to Debian, and eventually got to a point where instead of trying a different distro when Debian broke, I would just reinstall Debian.
I’d be interested to try VanillaOS or another “immutable” distro at some point in the future. See if they’ve matured enough for my day-to-day use.