So it is really the Windows 11 issues.
Either Windows dev or CS GO dev have to fix it.
It has been a month with no fix, sad.
Updates: lagging while pressing u /y to chat and in buy menu , after those thing closed no lag. Getting worse...
Anyone having the same issue?
I google it and found it happened from the past too, and it can be solved by restarting the CSGO and STEAM, but not this time.