Maybe that question is to clear out his doubts to use dome strategies he read up used by other people and same as you said there's nothing wrong to use it or any other else as long as there's no exploiting or other abusive things they do on the casino. To many people use that and experimenting other strategy to use and they are fine so they should try it since somehow those strategy mentioned is really fun to use.
You can use whatever strategy you like because it's dependent on your mindset but martingale is not too much fun if you have limited bankroll because of it's aggressive betting behavior in order to win but still we all have different opinions in gambling and for some it may work while for others it's the same.
It seems to me an important question is when exactly, at what moment the player decides to stop using some strategy that he uses before the next step in the game and switch to a new strategy or start playing completely chaotically. I think that this largely depends on the character and temperament of the player. And of course, on how lucky or unlucky he is in the next round of the game.
It seems to me that professional players approach the issue of changing strategies in advance, and this change can probably also be called a kind of strategy. But in any case, a chaotic game does not bring anything good, and even more, it is not as interesting as a game with a strategy system that every serious player develops for himself from his own experience or even intuition.