She clearly is. But I find it forgivable, since the article is actually fairly interesting.
And unlike most people who use the term "sexism", she actually carefully defines her terms. If a normal person says "a pullup bar is sexist", we'd think they are crazy, since we'd be find the moral judgements that person is making to be nonsensical. But because we know her definition, we can simply acknowledge "by your unusual definition a pullup bar is sexist".
I think it depends on the context of content. If the article were actual research then having contextual terminology is acceptable. However, when the article is read by a general audience then the contextual terminology should be simplified.
The title is very clickbaity, and the author admits as much. I would have flagged it as yet another silly piece, but I clicked and saw the author's name. I'm disappointed she'd drop to a cheap title, and I disagree with the premise that it is sexist. At least for any useful definition of sexist. The way she paints it is like that person that claimed her phone was sexist because it was too big for her to easily take a picture with.
However, there is actually substance there, silly "provocative" title aside.
The content of the article is reasonable. Men and women have different biological tendencies and that is likely not the first thing to pop up in a device designer's mind (if at all).
