Is it me or does TF2 look very noisy? Or is it some kind of film grain?
It's Source, so you have either a bad TSAA (seems to be used on the shots above) or MSAA for AA. 8x MSAA pushes my GTX1080 below 60 fps in 2560x1600 so my shots were MSAA 4x (gives you some 20% of performance for almost unnoticeable quality loss) and TSSAA 2x (doesn't really help with transparency aliasing but just adds detail to transparent textures mostly).
Either option doesn't really help with aliasing as much as I'd want, TSAA adds a lot of blurring but fixes some temporal crawling, MSAA does nothing for shaders aliasing. All of this ends in noise.
Edit: the game also doesn't allow you to use any DSR resolutions for some reason, even desktop DSR trick doesn't work. I've also tried forcing SGSSAA, the results are sub par as there's still aliasing and performance tanks obviously.