Banning gambling will lead to the popularity of illegal gambling platforms. Gamblers will always seek means to satisfy their craving for gambling. The use of VPN and other anonymity tools is common in such countries. But banning gambling will help to reduce the rate of new gamblers since there will be less advertising. And when gambling is not promoted it will not reach a large part of the population.
I come from a country where gambling is banned and prohibited, but let me tell you that people still gamble. There are mobile apps that allow you to gamble, without the need for KYC or anything, all you have to do is install an app, deposit money using your mobile wallets that we have in our country, and start playing immediately, and if you win, you withdraw in the same mobile wallets, without any KYC unless the amount is significantly high.
Now, let me tell you that even though advertisements and everything are banned, people are still doing it on Meta. I see multiple such ads every single day, and as far as I know, Meta doesn't allow promoting such things, but they somehow bypass that and run their ads, and they get customers that way. So many people gamble on these platforms, and lose a lot of money, government gets nothing because there is no regulation, and these private companies or individuals earn all the money through these businesses they are running.