Native resolution looks very pixelated?

My picture has always been pretty pixelated in the games I play (Fortnite, CS: GO), even though I play on 1920x1080. This is the native resolution of my monitor (AOC c24g1). Before I had this monitor, that was the problem.

My Gpu is a Gtx 1060 6gb and before I had a gtx 1050 2gb (this was the problem too) I play on quite lowen settings, but even on ultra this problem is present.

Connection? Probably DisplayPort right?

Yes, display port so I can use G-Sync ;-)

And the 144Hz. Have you ever tried to play with scaling?

Yes, with the individual scaling modes… So blackbars fullscreen etc