Mastery lock?

Am I the only one who thinks we should have a mastery lock on certain difficult champions? Like maybe mastery level 4+ for a champion that Riot deems difficult. Since I've seen multiple Katarina players who are mastery 2 and have seen a flyerbeck video or some other youtuber, and suddenly think they're the "shit" with the champion. It genuinely ends up causing games in a lot of situations since they don't know the matchup or the combos for that matter.