Some are fanatics. On this server I play on they change their skin to bronies, they all live in this brony town, they all do brony things together, and even staff has to get on to them for their outburts in chat. I can't really stop you from being a fanatic, but if I have to kick you from the server because you are causing a scene than it becomes an issue.
I agree with the statement here. Seen it on multiple minecraft servers. However, I have never thought it appropriate for boys to be watching that show. Especially older men. This is just my opinion, and I do not condemn those who watch it. My little brother is a brony so I have learned to tolerate it. Still doesn't change my thoughts, though.
Multiplayer session servers are down rn. Nothing is wrong with your client or your server. If you can't connect to your client that means that login servers are down as well. Always check the help page on minecraft.net they tell you the current status of their servers.