If you want a privacy focused VPN then Mullvad is great.
If you want one for torrents then it’s no good.

I mean a whole lot of horror movies would end in 5-15 minutes if the victims weren’t idiots who decide to explore the obviously dangerous “thing”.

I haven’t tried Sync-in but if simple is what you want then a Synology DS225+ should get you up n running quickly.
https://www.androidpolice.com/synology-as-a-google-drive-alternative/

Which part of the seafile install was it that made you back off?
https://manual.seafile.com/latest/setup/setup_ce_by_docker/

Depends on which Piefed instance you’re trying to contact and for what reason.
In the cases of feature requests a good place to start would be piefed.social/c/piefed_meta - !piefed_meta@piefed.social

If it’s about contacting a specific piefed instance then check their about page, f.e.: https://piefed.europe.pub/about

If it’s about helping out with developing etcetera then this page has links that will bring you to the right place: https://join.piefed.social/

That was an interesting read.

If you wanna own your audiobooks you might wanna check out https://libro.fm/ - they allow you to download the bought audiobook without drm.
I gladly accept tips for similar sites when it comes to buying ebooks.