I have only used Plex very briefly before I moved to try Emby then Jellyfin. Granted I am not a heavy user of a media server - basically no one else in my household uses it, and I don’t have a lot of content, but I do use sonarr / radarr with it.
The moment Plex put me off was when I realized a Plex Pass was needed to add transcoding capability. What are some of the reasons people like Plex better than Jellyfin, other than those who have been using Plex forever and are just too lazy to explore other options?
IIRC, once you install the plex server software, it sends you to the server’s login page to complete the setup where you link the server to your account, so you actually never have to enter an ip anywhere. Following that, you can log in to the plex.tv website from anywhere and get access to your media (as long as your router allows upnp), no need to set up reverse proxies or get your ip or anything. Then if you want to share your library with friends, all they need to do is make a plex account and you can give them access via invite links.