Honestly, I can see that being the perception, but frankly, I put a lot more people into the alt-right category. In this case, Richard Spencer is the alt-right of the alt-right. The vast majority of Trump voters have or had no clue who he was. Spencer gains from Trump, and encourages everything he can to move to the right, and is gains the most from notoriety that the media gives him in connection to Trump.
I'll agree with you that there is one major momentum of anti-left backlash. It ranges from disaffected liberals like Dave Rubin to ethno nationalists like Richard Spencer. I also agree that the alt-right is sort of the anchor, and in a way sets the tone of the whole thing.
The thing I disagree with is being too fuzzy about where you draw lines when it comes to particular stances. In a way it's their own damn fault for flirting with the alt-right earlier on, but the alt-light are not ethno-nationalists. I think that is important because people dismiss them for the wrong reasons. (Not to mention people like Ben Shapiro who were wise enough never to flirt with them, but who get pulled into the alt-right label anyway. All the while ironically getting harassed by the alt-right online.)
This is just because of the large volume of people who don't really understand that people who disagree with them are not a unified logical block, and they label all such people "conservative" and hate on them equally.
