When I was playing on 144Hz TN with anti-aliasing (AA) + 140 fps cap, I didn't have the problem with big gpu usage, it was never above 90%.
But when I switched to 240Hz IPS which Im talking about, then I unlocked my fps to have more than 200 fps+ but I realised that my gpu is much often near 97-98% usage, I could lower it by only capping fps to 140.
But that is not the final point... One guy on the stream told me that Anti-aliasing which I was using in the game (highest one - Filmic TX2 - in CoD MW 2019) is causing the most work for the gpu. its a killer for 240Hz Monitors. Even if I had all other settings turned off or lowest possible - the AA was causing most problem
I get used to highest AA because I don't like jaggy edges and moving pixels everywhere on the map, thats why it was hard to me to get rid of that
But I realised when we want as much FPS as possible we need to get rid of the any form of AA, because its either AA with max 140 fps (to don't have often 97% gpu usage) or just turn off AA and have less gpu usage + have easy more than 140 fps+ which is neccessary for 240hz monitors
Also I heard that AA cause slower rendering screen. And with turned off AA i actually could react faster and see enemy fly faster from behind the wall
Now I can play on my 240Hz with capped fps at 200 (thats my AVG fps) + never have more than 92~% gpu usage - because on capped fps at 200 with AA i had always often 97% gpu usage anyway, even at 170 locked it was the same, only at 140 fps at 240hz with AA I had less than 90% gpu usage... but who would use 140 fps just to have AA...!?
So AA was the problem.
I went further and also checked my 144hz TN monitor, it has 2x higher response time (!!yes!!) and 2,5x higher input lag compare to the Asus VG259QM 240hz TN which Im using right now.
So guys...
All pro's can use unlocked fps and dont have the input lag problem but actually they can do that only because they do not play with AA and all settings are low... and they gpu usage is not more than 95%
I thought im same like them because I also had the low settings as possible but only except the AA, which I didn't know gave me almost 30+ more fps and lower my gpu usage.


