I think the whole "Generation Z are Neo-Nazis" notion seem only applicable to young white boys. Most young people are apathetic or not very interested about politics in my own experience, so those 4chan and /thedonald users are probably very much a vocal minority.
Yes, remember that if Youtube Comments and 4Chan were your sole sources of information on the 2008 election, it would have seemed like Ron Paul was on track to win in a landslide, and the Alt-Right is popular among basically the same demographics Paul was.
