I mean, of course, sports betting. In casino games based on chance, such as roulette, many more people will not be able to get rich - 99.9% or 99.99% or even 99.999%. There are many prerequisites for such a forecast. On the one hand, we know the statistics, although they are contradictory. The overwhelming majority of players, approaching 99%, according to various estimates, lose money in sports betting in the long term. If you ask me for links to studies, then, I'm afraid I will have nothing to show you. This is very difficult to do and difficult to achieve truthful results. Not all players are inclined to tell the truth and it will be difficult for an outside researcher to verify. However, the longer the period we take, the more likely it is that the winners are only people who were lucky. So I wonder what motivates people who want to get rich on sports betting if they believe in such a pattern? Do the players sincerely believe in their own exceptionalism and genius?
Winning on gambling and getting rich through gambling are different things. Even though you could maintain a winning streak or have a good profit from gambling, you can't get rich from it. For a gambler to hit a large win, they should have a good bankroll to bet with and be lucky.
For luck based games like dice and roulette, the longer you keep playing, the lower your chances of being in positive. Mathematically impossible when you do it for long term. But for sports betting, there are people that claim to be earning from it but in order to get rich, they either need to be lucky with risky bets or start with larger bets itself. So, no people could make a living from it but don't get rich just from it.