The results from Alabama indicate that young voters aren't turning into Nazis in hordes all loving Trump. In Alabama. Seems kind of odd to conclude the entire country will soon vote like Alabama does now currently in terms of racial demographics.
Why does everyone say Alabama's GOP trend applies to the whole country? It doesn't make sense. California whites are trending Democratic. I see the CA GOP falling into a bottomless pit. I predict the 2020 Democratic nominee will win CA whites (and every other demographic in CA) by a wider margin than Hillary Clinton. I think the country is too diverse for all whites to vote like they do in AL. I think trends will continue to be different in different regions. Alabama is no indicator of a national trend.
Actually it did seem like the voters who put Jones over the top were the kind of voters that are fueling a backlash against Republicans nationally. Millennials, minorities and white college graduates. It is also true that even in 2012, Millennials in Alabama were much more Democratic than older voters.
So trends in Alabama can be exported elsewhere, to a degree.