- top tier mobility (fast base movement plus W active)
Her mobility isn't actually that good at all, stating top tier mobility would imply that she has mobility on par with Lee Sin, LeBlanc, Ekko, Ahri, etc.
Her Base movement speed is 340, which is actually pretty average for melee champions. Furthermore the movement speed buff is 2.5 seconds long every 24 seconds until you've build CDR, as nobody maxes it first or even second for that matter.
She's a tank, no shit she has top tier defensive stats it's the purpose of being a tank.
- top tier CC (E stun, Q slow, R)
Well first off she's supposed to have CC, again, she's a tank so complaining that she has things that tanks are supposed to have is kind of absurd. Furthermore the E stun is completely avoidable by not standing against walls, second the E Slow isn't that bad at all, and I've seen poppy's R be a detriment more often than an asset.
- INSANE DAMAGE without building a single offensive item
Half of her damage is completely avoidable, move out of the second half of Q, don't stand on a wall to get stunned. That literally cuts her damage in half. You know who else does insane damage without a single offensive item? Just about every other tank in the game right now.
there is NO COUNTER to this champion. you can destroy her in lane but the player needs literally nothing to group and carry the game. how again is this champion balanced?
Actually there's a number of champions that work well against her both in and out of lane, typically they're tanks that offer more reliable CC or other things to the team. Champions like Malphite, Trundle, Sion, Nautilus, even Darius does well against her.