The problem with intersectionality--a graphic illustration

It seems that the hip word on the left today is intersectionality.  I think it is a problematic concept.  It is a long word and not in common usage.  I am doubtful that  it leads to clear thinking or good strategies.  It seems to me that it is a progressive version of
"proactive" or "think outside the box." (perhaps the most inside the box phrase of recent decades.  I think is less useful than "coalition" or "alliance."

Intersection has, I think, two meanings that commonly spring to mind. Neither makes this a useful term.  First, when two streets come together. Second, in mathematical set theory-- an intersection is the set of items that have both characteristic A and characteristic B. I don't think either helps to make "intersecrionality" a politically useful term.

Here are sets A and B.

And, here is the intersection of A and B. Those items that are members of both A and B.

In contrast, in a set theory, the union of A and B contains all items that are a member of A or B.