I really don’t care what anyone says. Mei can be the counter to dive that the game needs but for whatever reason, they are scared to buff her…
While Mei is freezing you and her ice is landing on you, (and if you are caught in her Blizzard) you need to be locked out of movement abilities. The second her primary fire misses, you are not locked out. Mei would actually need to aim and land her primary fire on you until you are frozen.
And not passives. Just movements. Blink, Dash, Sprint, Boosters, etc. Imo, Mei will NEVER be where she needs to be until that is a thing.