That's not how the real world works. Parents have a lot of responsibilities, and watching every moment a kid plays FFXIV is the dumbest thing I've heard in this thread. You're insane if you think parents won't let teens play a teen game w/o supervision. Blaming the parents is essentially an extension of victim blaming.
Lying about your age is easier than doing anything else, which is the point. Asking for someone's age does nothing. Anything more actually forces the minor to commit to the lie and it actually makes the story of the fool that fell for it more plausible.
Playing the ignorant card is no excuse. You are already doing something that is not only against terms of service, but you are doing something potentially illegal in many countries.
Throwing up your hands and saying "nothing can be done" is why groomers are emboldened, as SE is put in a bad position. Don't say no one is willing to put a stop to it, because many people actually care about kids.