The following question is meant as an illustrative example of a more general pattern.
When a feminist talks about men, who do you think of, and who do you think they're thinking of?
I'd guess that, in typical Internet discussions of gender, most of the loudest voices are imagining one of two groups: either white cis heterosexual middle-to-upper-class abled conventionally-attractive men between about 16 and 40 years old (powerbros), or white cis heterosexual lower-middle-class abled conventionally-unattractive men between about 16 and 40 years old (neckbeards).
These two groups, even together, represent only a tiny fraction of all men.
Even among people who pursue social justice in good faith, there's a consistent tendency to erase and overlook people lower in the kyriarchal power structure.1
It has been observed2 that the term "intersectional feminism" is problematic, because although it acknowledges the existence and importance of a variety of issues, it still implicitly gives special importance to feminism.
Even "intersectional social justice" is not quite satisfactory to me, because it suggests that intersectionalism is like a plug-and-play addon that can be appended to social justice as an afterthought. I believe that a valid social justice must grow in the soil of intersectionalism from the start, or it can never be truly healthy. Intersectionalism must be more than a modifier adjective; it must be the noun, front and center.
Furthermore, if you pursue intersectionalism, you get a healthy social justice automatically, for free. It makes more sense for the concept of intersectionalism to replace the concept of social justice -- it fulfills all the same functions, but better.
I propose that we start calling ourselves "intersectionalists".
Intersectionalists know better than to explain an individual's behavior based only on the fact that they're a certain gender, or race, or class, or sexual orientation, or so on. Although these individual categories can be useful when talking about large populations in aggregate, we remember that the prototypical example of a category -- the first example to come to mind -- is never representative of the whole, and often unrepresentative even of the majority. We may not always get it right, but we name intersectionalism as a goal worth striving for.
The label of "intersectionalist" is an attempt to help talk about these issues, and thereby to help address them. What we can name, we can notice; what we can notice, we can start to fix.
1. This doesn't mean they're evil, it just means they're human.3
2. I didn't save the link, sorry. Anyone who remembers what I'm talking about, please feel free to speak up.
3. Though some evil people do exist, and some of them like to pretend they support social justice.