Unfortunately it looks like that one is for Apple devices, whereas I use Linux on desktop and Android on mobile.
There's some, but I haven't seen any that have the main features Plex and Plexamp have:
- Cross-fading when playing random tracks, but gapless playback when playing an album in order
- Analysis of the music using a local neutral network, such that you can tell it to play play "similar" sounding songs to the current one
- Automatic playlists - liked songs, decades, etc
- Downloads for offline playback
- Multiple libraries, for example I keep regular music separate from DJ mixes
- Equalizer with presets for common headphones
And probably other things I'm forgetting.
Should the USPS/AusPost/your local postal service be allowed to cut off a household's postal service because someone received pirated CDs in the mail? That's essentially the same thing. If anything, internet access is more important than mail these days.