I play Gran Turismo 7 on my steam deck via Chiaki. Wish they wud release on steam but for now this works.

Its more about being a disadvantage when you are the one lagging.

Uhh. It matters a lot. When someone hits the ball and your client thinks it went one way then the server thinks it went the other way, the ball will rubber band. Over the course of a match tens of such events can add up and cost the game. Try playing at 150 vs 8 ping.