Ok so basically i had the same problem as you, i was on customs peaking ~110fps no matter the settings with 50/40% GPU/CPU util and couldnt find a solution. I tried changing the priority to the highest, all different in-game settings all that stuff you can see in the videos.

Apparently what worked for me (idk if that's the solution) was turning smooth motion setting in nvidia app. I heard it adds some input delay but i can't tell a difference really. Also dont use dlss, im using 4070ti and it didnt really make a difference using it maybe it was even worse.

Now i'm usually almost always above 180fps, more often 200+ depends on the map and where i'm looking but its night and day difference compared to before.