Yea, no. In my opinion, annie is probably the most OP champion in the game. I ban her every time I'm first pick.
AoE CC burst. In what fucking universe could that EVER be balanced? Imagine Talon's ult stunned you. That'd be retarded and everyone would cry for nerfs because AoE burst with 0 chance of retaliation is just simply unbalanced. The fact that you can't even last hit in lane against annie unless you are above 75% health is just plain unfair. It's not fun to play against, and It's just too strong. When you land a big ult as malphite and your team engages, it feels like shit when the enemy annie just presses RW and stuns/bursts half your team to 3/4 health while they get cleaned up by the rest, not even mentioning that she can just kill any squishy that gets hit with her R with a Q.
Itemization also lends itself to her in a way that makes her annoyingly tanky. With a RoA, rylais, hourglass, and abyssal scepter, annie easily attains 180ish armor, over 100 mr, and 3k health.
Her 0 mobility problem is compensated for with distortion/mobi boots with utility masteries, meaning if you aren't in bronze and your team isn't just araming it and teamfighting every time they respawn then you will have flash up for the majority of important teamfights.
Everyone's common argument is that she's "low range" or "easy to zone" or "just buy banshee's veil hurr durr", which again is not true. She has 625 range on her Q (which she uses to last hit, might as well be her AA) and W, which is more than enough to easily punish any mage/assassin who does not have infinite mana and or infinite waveclear. Going all in on her is a death sentence because of her low cooldowns and insane damage. Banshee's veil can be popped by any spell, which you're guaranteed to be hit by plenty of in a siege, and has a 30 second cooldown. If the annie is stupid enough to engage on 2+ people with a banshee's veil that's just user error.
I have played many champions vs annie, and I just can't stand it any more. She beats everyone that isn't malzahar or ap kog and she is just so impactful that there's nothing you can really do to stop her. I ask her to be banned every game, and if she gets through and is picked on the enemy team I just dodge because i'd rather lose 3 lp than 20.