Or just via common fake IDs that certain vendors will happily take, since it provides the vendor just enough legal protection for reasonable doubt.
Keep in mind that the new market for black market products is quite small (only people between 18-20), and the cost/risk of setting it up quite high. It could happen, but I think there are better alternatives to bypass this block-aid. It isn't really comparable to prohibition or the war on drugs, as those were/are global bans Vs. the entire population.
Regardless - it’s a win for you I guess - but does anyone else’s opinion matter?
That's not how that works. At all.
If you get 1 less person to vape, but you get 3 people who were vaping seriously sick / they die from black market goods, that's probably not a net win.