if he knows gambling hurts him why should he follow it. not many people are ruined by gambling. he knows the limits in gambling. He should be an adult at that age and can think about that. but if it's like this, wouldn't it be a good idea to take him to a psychology doctor? I'm sure that can help him.
But it seems he will learn from his mistakes, sometimes gambling requires failure and loss to enable him to learn better in the future, I'm sure he will stay away from gambling and really think that it is a game full of risks and he will not touching him again after his defeat, I have felt what he felt since the first time I played gambling and was taught by my friend who encouraged me at that time.
I don't blame my friend at that time for encouraging me to gamble, it was my fault, because I was the one who decided and had the choice to refuse it, but I continued to try to gamble and ended up losing so my money ran out and in the end I could only be silent that I was wrong gambling with the desire to get rich quickly, apparently gambling is not a place that can provide instant wealth, that's clearly a lie, I hope he learns a lot after that because crying is also useless