The fact that both these games outlaw certain thought processes, be that counting cards in your head or acting on your partner's hesitation, shows that they've been shoehorned into something they're not.
Adding intermediation (either other humans or computers) removes most of the problems.
Perhaps, but that just reinforces the notion that the game is fundamentally broken. If a card game works better on computers, then it's not really much of a card game, is it?
The fact that there's something to "suspect you of" is the whole problem. Doing the same (counting cards) in poker is explicitly encouraged, and the ability to know what cards remain in the deck is highly prized.
Blackjack is just not a very well-designed game.
Unless you're referring to the basic skill of determining odds to make a certain hand based on your hole cards and the common cards?
Perhaps you mean that casinos in Atlantic City actually will not kick you out if they suspect you're counting cards, or they're bound by some law to allow you to keep playing?
If counting cards were actually illegal, we'd be a lot further along on our way to Orwell's 1984. You can't outlaw thought (yet).
The weird thing about card counting is that casinos want the people who are bad at counting cards. So it is not a flaw in the game, but just a weird rule that in the casino world you are not allowed to win.