I meant that for sizes at or near the ones in OP you can't really consider folding KK preflop.

I was talking to an opponent on the table the other day and he told me about a hand he had where he opened AA at 1/2 nl utg to 12, got raised to 90, got 4 bet to 240, and then shoved for 900 effective when it got back to him. If I'm the guy who raised to 90 or 240 in this spot, I'm folding KK vs the average opponent. These moments are rare tho imo, and folding KK when you're actually ahead of opponent ranges is a lot worse than just making the standard call it off and lose to AA approach, which is just a guessing game that you don't have to participate in.

Your size down argument is unfavorable imo. You're missing value from AK (which would often flat) and QQ/JJ that the average player isn't capable of folding pre, but would fold when overcards hit. You size down specifically so you can fold to AA (questionable in the first place), but there are a lot more hands you're getting action from that aren't AA.