What? Hojlund scored 1 header for us in a post season game. Thats it. Nobody suggested that other players are getting headers because hes being marked. You're more likely to find posts complaining that he doesnt have to be marked in the air
Another factor is Maguire was not playing. You tell me then, you're the opposition manager, we have Mbeumo up front isntead of Sesko - why is Casemiro winning a header? We have nobody else to be concerned with. They could put 2 players on Casemiro and be fine. But because Sesko is a threat in the air as well, Casemiro has more space at the back post