I've had a basic DLNA server running for over 5 years and just set up jellyfin about a month ago and it's an absolute game changer. It has the functionality of a good streaming service except using your own media. It searches databases and matches it to your files so you get some really good images with the interface and information about the media. Plus it remembers what you've watched and how far you are into episodes and movies. Which is perfect if you have two or more TVs or devices you watch on.
It's changed my partners preferences on how they watch shows. They hated watching anything on my server because they have ADHD and it's impossible for them to figure out what they were watching and where they were in it, not to mention trying to navigate my lack of organizing anything. Jellyfin fixes that. Now I just plop a show into the shows folder, or a movie in the movie folder and it's dealt with.