Not the parents, not the government, but I think the gambling site operator itself should be strict with the KYC process. In most usual cases, KYC should require selfie verification. I wonder how these kids now will be able to breach that verification.
Often times it is the parent's negligence that leads their children to access and play on an online gambling site. Working parents can find online gambling as means of their relaxation, they will play at night after work and forget to log out of their account when they stop playing the worst they use the PC that can be accessed by anyone in the family. Children, when using the same PC can accidentally discover that gambling site and start playing with their parent's accounts. That is one of the hows of these kids playing on an online gambling site.
That scenario could happen, and that's totally an irresponsible act of a certain parent. I find it more convenient gambling using mobile than the computer and it's more safe from the children getting exposure from any gambling website when you're playing on your laptop or desktop.
But of course, the gambling owner must have their fair share of responsibility for keeping away the minors from playing on their website.