He is bypassing the ban by his internet service provider or Government, but not the ban by the casino. There is a difference. If your Government bans gambling, for example, but this crypto casino lists your jurisdiction as one of those whose citizens are allowed to use their service. Then they don't give a damn what your ISP or Governments thinks. All you have to do is just get a way of bypassing that ISP block.
The scenario is totally different if it's the casino banning your jurisdiction.
This is like what I experienced where the government banned gambling... but in the jurisdiction of the country's crypto casino it is still allowed to play at the casino because almost all internet ISPs in my country block gambling sites, so the way to bypass the block using cloudflare.
Yeah it would be a different scenario if the casino jurisdiction banned your country. It is certain that in the future it will get into trouble because of the ban.