Pogba missing Manchester derby for that just feels unjust.
Boot wasn't high, although his studs were showing. Pogba can feel hard done by, although I wouldn't be surprised if he got an extra game ban for clapping the decision as well.
Just for the point of discussion - if it isn't serious foul play ("a foul committed using excessive force") and you assume he didn't do it purposely (violent conduct) then there's no law that says it should be a red.
Edit: Having watched it a few more times it has to be a red, he lunged for the ball more than I thought he had so it wasn't in stride like I'd thought.