The best is to gamble less so that we don't become too addicted to gambling looking at how so many gamblers are getting worse everyday in gambling. The reason why we will keep seeing so many gamblers having addiction is because of lack of discipline.
I align with your view, if gamblers could overcome excess gambling by gambling less, then their gambling issues are half solved. They can truly do it with discipline and it should reflect in their wagering amount, daily betting limits (time and number of betting) and overall gambling plans and management. This is not an easy task for some gamblers due to the situation they find themselves in, as they are so desperate for the money for one reason or another, not knowing that gambling is the wrong door to knock.
I think that action will most likely only be able to be done when they already know and understand what and how gambling really is as a whole and from various sides, especially from the risk side, actually without us having to tell them to do it, they will definitely do it if they understand the basic things about the concept of gambling as you exemplified, one of which is minimizing or setting limits on the amount of money and betting time. But it is a fact that unfortunately there are still many gamblers who find it really difficult to do it and sometimes even though many people have suggested it, they still can't do it, on the other hand this is also one of the reasons why addiction is really difficult to overcome, actually it's not difficult but because there is a lot of rejection from the gamblers themselves, when you tell them to set limits or stop gambling, it's the same as telling them to do something they always want to do.