In the past we had decentralised gambling platforms in which people of any age can spend their money gambling. Nowadays those aren't available anymore and everyone signing up is required to fulfill KYC.
There were many no KYC crypto gambling sites before, but later many prefer to require KYC. There are web3 casinos now which people can still use. Some web3 casinos come to this forum but their announcement thread is moved to altcoin board. Some casinos too are non KYC but people are not really trusting no KYC gambling sites like before as reputable ones are requiring KYC now.
Through this the underaged ones can be restricted from using the platforms. Even this is being bypassed with the verification details of parents or closer ones who are at the legal age to gamble. Underaged people gambling have brought big wins and there are examples of winner handling it in a mature manner. Same time there are people who end their lives after big losses.
Maybe they stole their parents documents for the KYC purpose, I do not think any parent can let their child to be gambling, not to talk of given the child their identity document to be used for verification. No matter what, underage can not win the gambling site just like adults.