We have to be ready that maybe somewhere in the future, KYC will be asked by the gambling site not just because of usual big-related winnings, accounts being monitored doing some unusual behavior, or any related cases that can trigger their alarm and security.
However, I have to disagree that complying with the KYC is a stupid thing just because crypto-gambling is supposed to be anonymous. There are lots of reputable gambling sites around where even though there's the possibility of asking for KYC, still not a mandatory thing to do.
You don't have to wait for the future, KYC is already made mandatory in many casinos. In some casinos, where you are allowed to deposit or play with KYC, they won't let you withdraw unless to perform the KYC.
Since the main purpose of gambling is to earn and then withdraw money. If you cannot withdraw large amount of money with KYC, then it means that KYC is mandatory though casino use it in their favor that they let you deposit without KYC but won't let you withdraw. You can call it as a cheating by the gambling houses.