When you mentioned he could have AA, KK, AKs, or QQ, think about it.
There are six combinations of AA
There is one combination of KK
There are four combinations of AKs
There are six combinations of QQ
(Even though AA is one hand, there are six ways you can make AA out of the four aces. It's better to think of possible opponents' hands as combos.)
Out of this, you can see you're dominating ten hands, beat by six and tieing one.
I know it seems like you run into AA so many times with KK (and it gets super discouraging to shove preflop cause you KNOW they have AA sometimes). But it's the correct move