Uh, first off the view is making it look like he is higher than he is.
Secondly his legs being tucked up also make it seem he is higher than he is.
His actual height isn't all that exaggerated. I personally can jump and completely clear an 4' obstacle.
Considering its a game, he should be able to clear at least 6', especially since jumping over somebody is sometimes required just for mobility reasons. and he really doesn't look like he's that much higher than that.