TECHNICALLY, accuracy does affect Critical hits!
You must be able to hit the foe in the first place in order to inflict a critical hit, but if you miss, there will be no chance at a critical hit.
So if Glaceon used Blizzard with a 70 accuracy, there would be a 70% chance of success and a 30% chance of missing.
- Within that 70% chance of success, there is a ?%* chance of a critical hit!
- Within the 30% chance of missing is a 0% chance of a critical hit.
Basically, the higher the accuracy, the higher chance of getting a chance at a critical hit.
But reality wise, yeah, accuracy does not affect critical hits at all. ~
*The critical chance rate varies, but at its first stage (with nothing modifying the critical chance) will be 6.25% chance of a critical hit.