Maybe the one who win and flex their winnings is just trying to win by betting in short time using this strategy. They just come and exit once they hit a good win then leave, this is somehow a good strategy since you didn't wait for the bad luck to came then been defeated by house due to our own greediness for using this strategy.
The same with other strat if you come up and bet excessively you will not gain anything whatever strategy you use so better they should think about that any strategy will not work for long term.
I am honest, I have played many times under the martingale strategy, I have won, I have lost, but it is not that I have lost so much money, I am not capable of putting all my available money to make a strategy like this, I think it is never enough to play with this strategy, because this strategy is very treacherous, sometimes one thinks that he will win and no, the opposite comes out, especially in dice, when one thinks that he already has only 1 move to win, he does not win, no I know if it is the same system that is made for that, for one to lose or for one to Quickly change the strategy and lose , but that Strategy is not good.
The main lesson we learn from that is we should never rely on so called famous strategies since this one doesn't give us any huge guarantee to gain more money by just playing. Also martingale is so tricky for the fact that there are times that we experience big heavy losing streak and we don't know what we are into since we expect to win because we believe that there strategies told us is perfectly time and we can earn with this passively.