Yes, some kids are so smart that they can bypass the parental guidance settings on the phone their parents grant them access to, but if the kids are always involved in gambling activities, they may not really keep a clean track all the time, and some observant parents can easily find out about it, while some parents are just too busy to even look at what their kids are doing. They maythink that parental guidance can do the whole job; they don't realize that they also need to be there looking at what the kids are actually doing.
Like you said, some kids don't realize the danger of gambling until they begin to get addicted or perhaps grow up with an addicted gambling lifestyle.
A teenager will need to get money somewhere to constantly gamble, and I’m actually not against the fact that if there is a lot of interest, the teenager tries to play, so that he understands that it is very easy to lose money in gambling, perhaps this experience will be enough for him to understand that everything here is not as simple as it seems, that in addition to luck you need to have many other skills, without which there is nothing to do here. I doubt that from playing several times he will get some kind of addiction, but I believe that he will be able to understand that it is not for nothing that this activity is prohibited until adulthood.