I believe the real question is: why is it that every time he has issues with players, it's those from another world and never those from the same world?

People in those servers might play differently. So what's considered rude to you might be completely normal there.

Furthermore, it's possible (I said POSSIBLE, but not necessarily the case) that the players in those servers might have a higher caliber of players. So while your skills might be fine for most of the people in your world, they may be lacking in comparison to the players there.

It may also be that those worlds have higher percentage of people who speak other languages and thus may not be comfortable writing out full sentences and stick to common acronyms (like BRD instead of your name)