However, there is a difference between "why" and "why", right? I do not question its "existence" (user count can prove that), but the reasons behind its being used - so I might be aware of things going on (user count itself can't add information about that).

Isn't that the case that people who want "some change" based on their (not too good) experiences - maybe sometimes they can't even recognize/express what they really need so accurately and what concrete things they are looking for - are likely to engage with new groups and norms which might just be a better experience for them - without any "formal requirements" and more like based on sensation? And the words/phrases/memes they "click on" are probably the same as other similar people "click on". And in that context "woman" might be an associative meme to these other memes: helpful, empathy, understanding, caring, respectful, misunderstood, minority. So explicitly using "woman" as a "meme" might be attractive to the people who are looking for or relate this other qualities/memes.

(I say woman as a "meme", because it's not for women only, so actually it seems to me it means more than its original meaning.)

This is just an idea how I can imagine what it MIGHT be about, any comment on that is welcome.