The problem with the story is Trump’s lead extends to likely voters in the polling. One of the basic definitions of “likely voter” is one who voted in recent elections.
So it is not clear how they reach their conclusion. Yes, the young did not vote in the last election. They were not old enough, but Trump’s polling results are not young dependent.
I suspect this is article is about black men, who maybe did not vote last time, but their numbers are not big enough to define the current Trump lead.