Gambling is one of these field where most people agree to regulate it, including the gambling companies, and it seems to be working decently well.

For instance mobile game gambling could have been way more rampant and destructive, but we have a decent set of rules and laws to limit the impact.

I can't imagine our society with 0 gambling happening, so if people will find a way anyway, I'd personally prefer it to be on the open, in a mainstream way. Blocking marketing wouldn't work when there are so many different forms of gambling, and obviously it also plays a social stabilizer role so I don't see any serious move to effectively stop people from gambling succeeding.