lagging

Is there anything to do against this unfair kagging?

How many games must   I lose because my oppenents lag so badly?

There was American guy who played 11 moves in 5 seconds. How am I going to win under theses circumstances?

lagging is cheating

Unfair kagging?

A person can make ~50 moves in 5 seconds.

If someone plays 11 moves in 5 seconds, he's using premoves.  Check it out:

https://support.chess.com/customer/portal/articles/1444864

And it only uses 0.1 seconds.

Just check your internet speed and connection generally If you lagging there Is somekind of issue with that. And no, a person cant make 50 moves in 5 secs, and thus an average of 0,1 sec per move. Only premoving allows that, and you can't premove 50 moves!