Yes, the possibility of addiction applies to everyone regardless of who they are, old or young, poor or rich, everyone has the opportunity to end up becoming an addict, and in the end the point is not much different from what you said that if we don't want to end up addicted then gamble wisely in the sense of gambling with full limits on time and the amount of money at stake.
Therefore, this is the reason why I often say and advise anyone, especially those closest to me, to first understand what they are actually facing, the way is to rely on a rational mindset in responding to gambling so that you do not misunderstand what is meant by the chance of winning in gambling, and if you have done everything well and correctly then I think you should be free from addiction.
The most vulnerable are those who bet on something they are not very good at, or those who are into slots, where I think it is almost impossible to win from a casino except for some random chance that I would definitely not rely on. And it also depends on how much the player is ready to take risks and how much money he is ready to play, rich or poor, they can equally lose all their money if they do not stop in time.
Yes, I quite agree with your opinion regarding those who are most vulnerable are those who are involved in an activity that they do not know, as the saying goes that before you jump into an activity, know and understand what you are actually facing, this will allow you to still be able to make the right decision in every situation because you know what you are facing, so that's why I agree with what you said that the most vulnerable are those who do not know what they are facing.
On the other hand, for the problem of winning in gambling, it is actually nothing more than a chance, there is no certainty whatsoever that we will always be able to end the session with a win, especially if we talk about slot games which as we know are a type of random game that cannot be won in one or two ways, the point is yes, rich or poor, they can win and can lose, or what is meant is losing large amounts of money or addiction also applies to both categories if they bet in the wrong way without being based on any understanding and knowledge