There are gamblers who makes multi millions from gambling, a particular man who owns some sporting franchises now made his fortune from gambling and he said he grew up watching his dad gamble and what made him better is correcting his dad mistakes.
I agree with you that gambling has made millionaires, but it's not about knowing how, but it's more of being lucky.
Gambling is fun but if you spot your mistakes and learn from them gambling can be a type of fun that keeps giving.
I seriously doubt if it's possible to be winning consistently because even though it's sport betting that analysis plays an important role in your chances of winning, your can't get it right all the time.
Furthermore, when you start taking gambling as a means of livelihood or a means to escape poverty, that's the fastest way to addiction because you will gamble more than you ought to, which is the easiest path to addiction.