It needs to educate the influencers so they will not promote gambling to public and there are a strict rule for them about promoting something. If the government can cooperate with the influencer and gives education to their citizens about the risks of playing gambling, maybe that can works and the citizens will not trying to playing gambling.
And for physical casino, they must strictly limit people and will not allow teenager to enter to the casino although that can not be apply to the online casino but the online casino can use the other methods to prevents teenager to playing gambling.
One of the most disadvantageous part of these public gambling influencing by popular influencers is that they do skip the part of sensitizing the teenager who mostly have little or no experience about gambling. They will not be honest enough to tell them of the negative effects of gambling but will rather concentrate on making them believe that in gambling, it's always about winning big and if these teenagers out of their ignorance decides to gamble, they mostly end up becoming gambling addicts and that's because since they were made to know about the positives of gambling, they think it's abnormal to lose thereby gambling more when they lose in other to win the desired amount.
My suggestion is if they must influence to the growing teenagers about gambling, they should be compelled by governmental guidelines to also sensitize the young ones about gambling addiction and how it can happen.