Hi Kinga, does this comment count as a reply? I hope this issue gets fixed.
Nevermind about this, I tinkered with this stuff for a while and figured out how it works. It's very weird the way it works. When using x y z in a command block, you are setting that command block's location to that point. If you then add dx dy dz, the number you type next to them will be as if you have added tildas to each one.
I would love if this got fixed
Not sure about other resolutions, but the horizontal and vertical sensitivity is different at 1080p. Left and right being faster and some inconsistent or weird acceleration.