Having no geographic restrictions is definitely one of the best features of cryptocurrency casinos since almost anyone from any part of the world can utilize the platforms and gamble with ease since there are also no restrictions on cryptocurrency transactions. This has given a platform to everyone to be able to play games without any restrictions.
But, I think there are still some casinos that don't allow some gamblers from some regions to play on their platform, this probably is because they require KYC for withdrawals and they are not able to verify some users based on their region.
That's not the reason, I believe any citizen around the world have their own ID card, so they can verify their identity. But some countries are not allow their citizen to gamble due to religions or their own choice. Usually casino are restrict some countries because of the providers, politics and licenses, that's when a casino have a lot providers, you will see many countries are restricted.
Although VPN usage isn't allowed, but some people still use it lol.