KYC can be solution to prevents the money laundering and other illegal things and even for people under 18 years so those people can't playing gambling on that casino.
But is that the only thing they can do to prevent money laundering? I honestly doubt any business provider care about that, they do all of these check because the government demanded them to do so. How effective is KYC from preventing people launder their money? Why not block transactions above specific value to begin with if they don't want to risk their platform being used as a money laundering spot? Another issue is how unreliable business data protection with so many data leaks, not to mention false positive or terrible system that failed to detect individual as a non-dangrous player because one or two things like faulty image processor.
You can doubt that but casino see this is a way for them to know their customer who playing gambling on their casino. Casino will still difficult to prevent money laundering but with KYC, they will know the money flow so they can investigate it by asking for more to their customer. Maybe casino will require more document if they found a suspicious thing while they investigate their members so they must know what is the real things that happens.
If casino block transaction for specific value, that will not be a good ways because you know that many people use big money to playing gambling. If you check on some big casino, you will see many big transactions to place their bet but with KYC, casino can check that and if they see that is because money laundering, they will warn their members or even block the account. Casino can report what they found on their casino to the government and let the government investigate furthermore. Casino just follow the rules from the government and runs their business.