Working between servers.
Just simple stuff like searching, adding, customizing feeds. Clicking an alert to take me to the content will take me to a server I’m not logged into and I need to go back and find the same post via my own server to comment. Not the end of the world for me but likely a big issue for many potential users if the are use to mainstream social media that ‘just works’.
Linux gives you freedom.
Freedom lets you break stuff.
If, like Windows or MacOSyou just use it as intended by official support, it should be fine. If you start just adding everything and anything from anyone you’re gonna break stuff.
Other stuff is made to be idiot proof, Linux is not.