I don't know man. Morata is a very good player imo.
Plus, like others have said, if de Gea wants to go, then the club's opinion becomes secondary. If the player wants to leave, it's better he leaves.
The one possible downside of this deal is whether Morata wants to be at United. It seems that he'd rather stay and get a fair chance at Madrid but is being forced out. Which, after di Maria, should be considered a red flag.
We should just get as much money out of it as we can and spend it on players who want to come here.