Why? The idea that a single player is going to run around and cover the pitch for Mainoo, de Ligt, when Bruno loses the ball and our stupid style of play where our other CM and AM abandon the midfield is flawed and not based in reality. I don't think even Superman can cover that amount of area on the field. Also, what happens when Ugarte is out injured or suspended or rested? Who will make a "tonne of sense" then?
If the player is, as per you, slow, isn't good in one on ones, not aerially dominant and only a 'bit better on the ball' than Maguire then nothing about his signing makes sense, forget tons of it.