Not to quibble too much, but the term Alt-Right was self-applied. It is a real, disgusting movement that is worth paying attention to. But to say it's not racially motivated is incorrect. Their own champions will tell you what it's about in their own words. The left is trying to bulk everyone else on the right in with them.
I recommend giving Ben Shapiro's show a listen (the first one after Saturday). It's got good stuff on Antifa and the alt-right.
https://www.youtube.com/watch?v=67zCG-KPWfQ&t=674s