Watch Sargon of Akkad's honest look at the alt-right. He is critical of them but not unfair:
https://www.youtube.com/watch?v=Cp0uq-QafYQ
IMO the alt right has risen in response to the regressive left. Born of what I believe are good intentions (not pandering to PC culture), the alt-right have attracted certain racist groups and people as followers. Just as the progressive left have the fringe feminazi, BLM regressives, the alt right have their racist bigots among them.