Casinos existed without the need for KYC's until the government made it a requirement, and they started demanding it. IMO If the government no longer requires casinos to do KYC verification for new gamblers, casinos will go ahead and still do KYC verifications because they have seen the benefits of knowing their customers better than when they just allowed people to come onto their platform and gamble without their knowledge of who they were. What do you think? Do you think some casino's will revert back to non-KYC and allow money launderers, plus other fraudulent people have their easy way with them as a way to attract customers, or since they recognize the personal benefits of KYC to their casino, will continue demanding it even if it affects their customers?
We do not really need to make any guesses to know what it will happen as we saw what it actually came to happen, casinos did not implemented widespread KYC policies until the governments mandated them to do so, what does this tell us?
That casinos are perfectly fine with letting gamblers bet as much money as they want without forcing them to identify themselves, as casinos do not really care about that information, what they care about is the profits they can make, and a higher level of privacy gave them an edge over fiat casinos they could use to their advantage at the time.
Casinos didn't have KYC policies before governments began to mandate it so I doubt that they can continue to demand it if the government doesn't need it. But I doubt that KYC requirement from gamblers is going to stop because of it's success in reducing money laundering so it has come to stay permanently. Casino owners are business people and they wouldn't care if criminals are gambling their money, provided that they're making profits. No business person will ask how you made your money when you want to spend it on their products or services, they're happy to collect your money and let the authorities worry about you intentions of patronizing them.