It doesn't do anything more for you than to stream your own media

Sure it does, which is why we're not all using VLC to stream our media.

Furthermore, they do provide a simple way to share our media with friends and family via their authentication servers along with their relay servers if direct access to your server goes down for whatever reason which have associated costs. I have a lot of my own gripes about Plex, but this particular change is probably at the bottom of the list, and I think acting like this software has zero value is disparaging not only Plex but Jellyfin and the army of volunteers over there working hard to make their product better for you and everyone else at no cost. You're essentially saying all their work is worthless since their product accomplishes all the same things as Plex.