I know Tom is arguing the laws but the laws are ridiculous. If McTominay had kicked Son in the knee with his heel as Son was running behind him nobody could say that McTominay 'used' his foot to kick him. Saying the same about a hand touching a players face because 'it's the face' doesnt make any sense at all. That was blatant simulation by any definition and Son was rewarded for his cheating by having a goal overturned. If Son acts appropriately and simply rubs his face then there would be no review and the goal would stand. He simulated an injury to affect the game. That's cheating.