Funny, you cut off the important bit right before that quote where the man cut her off as she was about to explain her most recent book. Here’s a bit of context:

“She began to talk about her most recent, on Eadweard Muybridge, whereupon the man cut her off and asked if she had "heard about the very important Muybridge book that came out this year"—not considering that it might be (as, in fact, it was) Solnit's book.

See how the context changes the situation? She was already speaking, and the man cut her off, assuming she was unaware, and explained to her something that he would have learned to be unnecessary if he had simply treated her as a conversation partner to be listened to, rather than something to be narrated at.

I can already tell I’m not going to be able to convince you, though. In order to support your point (and, perhaps, avoid any self-reflection) you’ve ignored nuance - generally bad practice when talking about the intricacies of social interaction. Certainly, men monologue to men, men monologue to women, women monologue to men, and women monologue to women, but much like when people equivocate the fear of sexual assault to the fear of false accusations, the thing being ignored is the amount that these things happen; they are not equivalent.

To be absolutely clear: I am a man. An autistic man, even. One who loves to learn, loves to info-dump, and has more female friends than male. In all my time info-dumping to my female friends, I have never once been accused of mansplaining, because I ask before I explain to ascertain their knowledge, and I actually listen when they speak.

Funny how that works.