wksks
Why does everybody play the london system?

It depends on how u play it... Higher rated players do more research on openings and find interesting ideas...

People play the London System because it's very easy to play, they don't really have to think about what they're doing. Their setup doesn't change no matter what black does, and they just put their pieces in the right positions, get the opening over with, and then think "what do I do now".
Lol.
Kamsky and Carlsen, to give two examples, have won many brilliant attacking games from the white side of the London. Most club players play it with no particular plan, and no awareness of the significance of the different move orders, but that's not the case at the higher levels.
London is for chess noobs
You know, Carlsen, Aronian, Karjakin, Kamsky, those noobs

I have noticed that london players usually play the same moves regardless what their opponent plays. Sometimes against me i blunder a pawn fork and they do not exploit that because the fork is not part of their setup. Usually they are heavy premovers. So if you want to be really dirty premove something stupid so that their premove can get punished. It is honorable but in my experience it works really well.
yeah, people typically play the london system more in blitz/bullet because they just do the same thing every time.
its a very boring opening imao