Why?

In my understanding fail2ban will block ips if they are detected to do brutforce or use known exploits.

Crowdsec will share this IP via a blocklist to all subscribte systems. You will benefit form the detection of other systems and not only your own.

The smarter the tech, the dumber the privacy agreement

I can recommend the video The science of catching up in life

Docker containerizes jellyfin. If you use proxmox you don't need to containerize in a "container".

I always wondered if this is possible.