In my opinion it's the governments getting unhappy that all nationalities can kill each other in a polite and friendly manner on the servers and going against their BS narratives...
The attacks are aimed at crashing the server. There's no compromise. If someone was to set up a "bad" server to the best of my knowledge it can't do anything to clients. The only things that the server can send to the client are game information by UDP stream and map/mod/static mesg etc into your cache from a web server. The unrealscript runs within a game-sandbox