I go on the server a lot, and sometimes work on my youtube channel, or play another game for a little while, while I'm afk on sneyersul. A lot of times I get kicked for idoling over half an hour, then I conducted an experiment, I stayed on the server, not being afk, and I got kicked for idoling over half an hour, so, what's the use of being afk?

It shouldn't kick you if you haven't been tagged as AFK for 30 minutes. The reason we have this is because people used to increase their play time by staying connected, sometimes for days in a row, without actually playing on the server.