Your hypotheticals are even more ridiculous. There are very few 7'4" people out there. Hypothetically if Edey was 6'9" he would likely play the same position. Your hypotheticals would put guys in a different position.
With that out of the way, his height and also his bodyweight give him quite and advantage. It's the thing that makes him effective, it's undeniable.
I don't anyone is saying he's a bad player.