One half of the dudes that do the Linux User Space audio/video podcast.
If you can do everything with Docker/Docker Compose, you free yourself from worrying about the underlying system. Docker becomes what you need to learn, and the worst part of a Linux setup is just getting Docker installed and updated.
Ubuntu would be my Linux pick, though. Long support, paid support if necessary, and a very large community.
AntennaPod is the best out there on Android imo.