The profitability I am talking here is long term, not short term as short term does not say consistency, it could be only due to luck.
I don't think that the gambler can get profitability in the long term because the casino will win the money. Maybe the gambler can win in a short time, but it will need to have more strategy or method to win. If the gambler can have luck, maybe they can win on the gambling games. But we know that luck will not stay for a long time, and when the luck is gone, that means we will get another loss.
It's better to analyze first the situation and strategize before deciding of which method can be effective like for example if you know that you have a small chance of winning then don't bet a large amount of money just stay in small amount in case you lose the amount will not hurt you too much and for example you are confident to win then bet a large amount and if you win and want to bet more then back to the first method. In short to minimize the loss of profit don't bet a large amount in a row.
Even if you feel confident in winning, it doesn't mean that you can win easily because sometimes, the situation can change, and we will lose our chance to win. Using a small amount will be better because you will not lose a big amount if you lose, but you should accept if you win only a small amount. So be careful to manage your money in gambling. Otherwise, you will not have your money in your pocket in a short time.