I don't think you understand what a legally mandated payout rate means. You can have a slot machine that is completely random, yet gives a consistent payout over a large amount of trials. Every spin is independent.
You are positing a situation like, hey, that dealer just dealt that player two blackjacks in a row. Therefore for the next three hands we're going to take all the aces out of the deck to make sure there isn't another blackjack. Obviously this is not how casinos work, neither is a slot machine adjusting its odds to hit a specific payout target. The blackjack game, and the slot machine, don't have to, over the course of millions of wagers they are mathematically certain to get very close to that theoretical target.