I use Plex. I have different libraries set up for movies, TV shows, educational videos, home videos, and during the pandemic it was great because my kids were doing dance class remotely, so I even set up a library so they could have all their dance class videos in one spot to practice their routines. I also organize my family photos there as well, which works out great to have those and the home videos all in one place. I can even give family members access to various libraries if they want to view family photos/videos, which has been handy as well.

Lots of people swear by jellyfin, but I've had so much success with Plex that I haven't bothered to check it out. It's probably easy enough to get a server for each up and running and see which you prefer.