^thanks for the detailed reply. Since Blackjack we are talking about here, the outcome of the game depends on the players decision too which gives impact to the game.
The house edge set is when you play the game flawlessly using the blackjack table matrix but it will varies and increase significantly if you play differently from the strategy. This accusation is very hard to prove since the game needs to be check individually for the decision making that he use on a single game. If the game is dice then it’s easy to conclude with huge sample.
I agree with you, house edge (or RTP) figures announced of Blackjack games are actually "optimal" house edge or RTP, that is to say, it's the figure you will get if you use the optimal strategy or the optimal decisions if you prefer (hit, stand, double down, split or even surrender if available) for each combination of cards you get against the dealer