It is spreading as a cancer. This month the central bank published a report saying that in August 20% of the Bolsa Família, the largest money transfer program for very poor Brazilians, was spent on these bets.
Out of the 20 million people that receive it, 5 million made bets during that month. This is 2 billion reais (about $450M) spent in a single month by the poorest Brazilians.
It's a cancer. Everywhere you go there are ads. The influencers, the biggest athletes and musicians are marketing it.
Although I tend to be liberal, this needs to be heavily regulated.
As a libertarian however, I break with the opinion of making consensual activities illegal even if they are self-harming. So I guess my stance is probably the same as addictive drugs. They could be legal, but come with the same labeling, warnings, ID requirements and age restrictions that come with a pack of cigarettes. We should probably be educating kids about the dangers of addictive apps like we once did with DARE on the dangers of drugs.
Now, the proportion of people who still take up smoking today do so in spite of all this, which is probably down to them having various specific user profiles that are unaffected by this (IE they live in communities/work jobs where its ubiquitous or are huge James Dean fans).
For gambling, you could possibly go a long way with awareness and labelling, but I think an issue is that gambling is a lot less visible than smoking. Nobody can smell that you popped outside to blow your paycheck on tonight's game. Making gambling deeply uncool might make some people not take it up, but most of the existing addicts would likely carry on in secret. They're already commonly hiding their losses from spouses and friends, so what's one more layer of secrecy?
At any rate, what worked for smoking wasn't making smokers quit, but making fewer and fewer kids start doing it, so making it a pain in the ass to place your first bet might help.