Hold on a second.
Annie's CC hurts immobile champions just as much, maybe even more, than it hurts mobile champions.
A champion like LeBlanc can at least close the gap in between Annie's stuns and get out quickly, but if it is a Cassiopeia or Varus for example, good luck surviving 1 or 2 more stuns while trying to run away.
Annie has as much counterplay as
, which is quite frankly a lot. However, until the enemy team can buy
,
or
, there is nothing they can do about Annie. (Unless they ran
of course)
Not clumping together is a good idea to mitigate some of the CC, but Annie only has to prioritize the carries, she doesn't care if she stuns the Mundo on the side or not.
Annie has high pick rate and high win rate across every ELO. When Annie can cast Tibbers instantly, there is no indication before she ults. Unlike Amumu or Malphite, it is too late by the time you see the animation play.
Amumu needs to land a skill shot on the right person or flash in to cast his ultimate. Malphite's ultimate has travel time in which enemies can escape. For Annie, it is just point and click the area you want to stun.