Plex is a taboo topic anymore because of their recent business-focused changes. I personally use Plex as I’ve been a user since the early 2000s with no intentions to learn the nuances of Jellyfin, and get my remote streamers moved over to it.

Plex mixed with Sonarr, Radarr and Overseer fits my needs perfectly.

It’s literally maintained by Fedora. Not sure why he claimed that.

I’ll raise you one and attach a mount point over iscsi!

I’ve been running mailcow for almost 2 years with no issues. I’m not doing anything major with it, mainly using it to send myself alerts on the environment, but it does work for external purposes if I want it to as well. Updating is easy and seamless. I did get greylisted almost immediately though, so I use SMTP2Go and it works great as a free relay for the amount of mail I generate.