I'm not sure if there is a strategy that exists as I think there is none and we got into winning because we have luck. The fact that we can't manipulate the game, strategies seem to be useless and no matter how skilled we are and have a long gambling experience still can't change how gambling works. Maybe if we are talking about trading or investing, we could find it but since we are talking about gambling, then would say nothing.
Gambling is not a source of income, so we don't expect such a thing "profitable" unless we are the owner of the casino.
Be it long term or short term there's no strategy that as been proven to stay profitable all along it could only help minimize losses and help your risk management be much more effective but then can never be continually profitable and default of losses, at some point you will suffer losses but then you ability to make good use of the profitable days to make money and cover for the losses makes the difference.
That is the truth, people will say this or that about gambling, but in reality, there is nothing like the strategy that will be profitable long-term without the addition of the right management and balanced psychology. Good, a whole lot of approaches to gambling could work in some sectors of gambling, especially if that aspect is fair enough and can't be wired much against the bettors. In this good strategy can still try so much, but in most, it is not like that, so if you rely on strategy in this regard, you will fail, you should only pray that you are lucky in gambling when engaging with them. For this, even if there is a strategy, there must be budgets and plans and the gamblers must ensure that they are disciplined with what they want to do in the gambling house/platform, not that they will just be betting and later be pained with the awful results they have.
Even if a strategy is not so good but the gambler is betting accurately and calculatedly, they will still limit the bad effect of the losses incurred most times and it is fun in this regard. In my case, most times that I place a bet, I have this good feeling in me as regards to the curiosity of the outcome, so I do not fear losses. Even if I lose, I do not bother much about it since it has been well planned and my account is also effectively managed, which does not cause any losses to be so painful to me. This is what really matters, not the view of having that long-term strategy that will be profitable but having that total style/system of gambling that will make gamblers survive for long.