Indeed, in most of the countries, restrictions aren't that with online gambling unlike with landbased ones. Therefore, engaging with social media advertisements would still benefit a gambling platform. Also, they won't spend money for something they do not know about so more likely those gambling sites who does so, have tested and saw the results of ads 'coz they'd be throwing their money if they won't know the negative consequences of it. Also, advertisement in any field doen't need to be too detailed. Recognition from players and potential players would be an enough result of social media engagement thru ads.
If I remember correctly, I think I read somewhere that Australia is about to ban online gambling ads from the country, and gambling platforms can't advertise their services online. Now, I'm not really sure if they are also going to ban online gambling platforms or if they are just banning the ads for the concern that it may lead to luring the younger generation towards gambling since we all know how enticed the young generation is with the digital world.
However, I'm not sure if that is the case with other countries and what their take regarding online gambling and their advertisements, but I feel most of them only allow casinos operating online with a valid license acquired from the licensing firms and authorities of the same country they are operating in.
However, any prohibition of gambling at the level of governments and laws of a particular country, in particular, as you mentioned Australia, will not lead to the fact that the younger generation does not become addicted to gambling. Such countermeasures always lead to only one thing.
A ban on gambling will only have the opposite effect, as the forbidden always entices young people to try, and in this sense, such government measures will not only be ineffective, but even harmful. Such a ban in this case acts as a hidden advertisement of gambling. But I think that what you read about the intentions of the Australian authorities to ban gambling is just informational stuff in order for the inhabitants of this country to simply pay attention to the problems associated with gambling and the emergence of gambling addiction to such an extent that such players should be treated. This is how I see the purpose of this information.
Moreover, the USA has already tried once to ban alcohol. We all know that this, one might say, scam turned out.
Here is a similar picture will be in Australia in the case of a legislatively adopted ban on gambling.