This is a great thread. I have had a home server for almost 10 years at this point for files & media, and added a second dedicated dev server this year. They both run FreeBSD and I honestly couldn't imagine my life without them. I recommend to people all the time that they get a home server, even if its just a used NUC, but not too many people do for whatever reason.
My file / media server has roughly 20TB online and has movies, games, books, personal files, etc served with NFS & Samba. I don't use anything fancy like Plex or Jellyfin, just XBMC which works fine. It also runs the usenet stack nzbget, nzbhydra, etc and has a virtual machine running transmission through a VPN. I also have a custom ruby script that transcodes files to x265.
Once you get into the home server biz, the most important thing is to have a great case. Mine is the Fractal Node 804, which IMO is truly awesome - a big cube that holds a microatx board and 8 drives, and its actually pretty affordable. For hardware specs, I started dirt cheap and then upgraded too much, building a 12-core / 64GB setup that sat at 10% CPU utilization most of the time. I've since downgraded to a i5-10600 w/32GB RAM which is more than capable.
This is beyond the scope of the question, so I won't get into details, but I would also encourage any developer to have a dedicated dev server as it helps you to better understand performance and deployment.