I don't know the rules of which country you are discussing in this topic, because as far as I know, every country has different rules on Alcohol and gambling. Admittedly, historically both have had their downsides, but if the level of risk posed by Alcohol is lower than gambling, then that goes against my train of thought (perhaps regulators in those countries have different reasons).

Alcohol can pose a big risk if someone drinks it and then drives a vehicle on the highway, someone who is drunk or who is in a subconscious state can do anything that is detrimental to others, even worse, can take someone's life. Even though gambling can lead to things that are detrimental to others, someone who is addicted to gambling does not lose consciousness like someone who drinks alcohol.
Moreover, gambling platforms also often appear on various social media and even professional football clubs have started collaborating with various gambling platforms and most players also want to spend their free time just to have fun, unlike the case with Alcohol, most of them don't stop until they are drunk. So, in my opinion restricting gambling advertising in the countries you're referring to doesn't have a significant impact.