Why don't top players think Mai is good?

I'm a middle of the road player, 1600 MR and I can't understand how she's not considered S tier.

She gets very cheap oppressive midscreen high/low/shimmy/throw mix. You can't hedge your bets and 'take the throw' as if you do that or guess wrong you're in the corner and she has one of the best throw loops in the game with auto-shimmy. She's harder than nearly anyone else to pressure because she has better risk:reward on her level 1 (gaining stocks to increase her chance of coming back in the round even if you bait it).

Other characters with this much easily accessible mix don't have EX DP reversals. They don't have a punish-anything-on-screen level 2 better than Cammy's level 3 when they have stocks.

What makes her weak at all? Her DP whiffs sometimes like Chun's? You have to spend meter to get her level 1 midscreen? I'm at a loss how people are dealing with this character.