Well you see, this post is about the ways in a nuanced explanation is inferior to using the phrase "Dumb Fuck!" because it has to be specifically written for a post, can lead to an exhausting back and forth debate where you end up having to write more explanations, can often sound condescending due to the inability of text to carry the subtleties of spoken language, and the length of them can often be too boring to read. Of course simply writing "Dumb Fuck!" has none of these downsides, because it can be copied and pasted into almost any situation, is very hard to debate against, is very cathartic, and loses no subtlety in text versus spoken language.
She might think you're being hostile just because she's a woman. That's why it's better to drop a gendered insult directed at men at the end, just to be sure.