I really wanted to post a screenshot to show this, because it’s much easier to explain that way, but I didn’t manage to capture one of this in action yet.
Basically if I am crouched up close to and behind a wall, with the wall taking up the bottom 3/4 of my screen and the sky the top 1/4, then other players can still see my head sticking over the top of the wall, whereas from my POV this should no way be the case.
It’s almost as if the best fix would be to raise the eye-level of players whilst crouched, but then many walls would simply not be high enough anymore, and it’s quite a bit of effort to go through all the maps and raise the height of them everywhere.
So perhaps the easier way to fix this is for crouched players to be lower to the ground (from the perspective of others) than they currently are.