Lets define our terms first. This article defines a serial dater as:

A serial dater is someone who dates many people in a short amount of time because they love the feeling of “the chase.” Basically, these people fall in love with love.

Another article defines the serial dater as:

The serial dater is one who loves the thrill of the chase and the excitement of the beginning, then jumps ship—to a first date with another person—before anything too serious can develop.

But wait, isn't the term "serial dater" gender neutral? Can't men just as often and easily have the same serial dating tendencies that women do? Absolutely. The difference is that the male serial dater is judged to be a "bad faith actor" in the dating marketplace based on his outcomes (and the label "fuckboy" therefore supercedes the label of serial dater) whereas the woman is outwardly judged to be a "good faith actor" in the dating marketplace based on her declared intentions (because no one is going to openly admit to traits that make them look bad).

Essentially, "fuckboy" has become a gendered epithet for a serial dater that is a man. I think a common mistake I see people make is that the stereotypical fuckboy is a Machiavellian master manipulator that knows exactly what he is doing when, in most cases, he doesn’t have an ounce of self-awareness. He is just chasing the next dopamine rush, same as the woman serial dater. His lack of self-awareness and empathy is by definition what makes him a fuckboy. And while most fuckboys declare themselves not to be fuckboys, the label remains.

The woman serial dater, on the other hand, has vastly more plausible deniability and can optically posture herself as an individual that does take dating seriously, even though her actions indicate otherwise. This of course makes it harder to believe the legitimate complaints women that do take dating seriously actually have.

We can try to be charitable and assume after dating a large amount of men in a short period of time that "maybe she did just have really bad luck". But that same level of charitability is not extended to the male serial dater. He is judged for how he has left the women he has dated feeling, instead of his intentions.

I think its also important to acknowledge that in modern parlance, the terms fuckboy and serial dater also carry very different connotations. The fuckboy is seen as some sort of pathogenic specimen whose destructive effects are already assumed and should be studied only insofar as their behavior can be outwardly deconstructed and avoided. The serial dater, on the other hand, is treated more like a person going through an "awkward developmental phase in their life" and that person must introspect in order to grow out of their "immature dating tendencies".

I believe a lot of this has to do with how dating is still seen as something men (as the active participants and initiators) do to women, when in reality the relative agency in the modern western world is much more co-equal. Having different sets of criteria (intentions vs outcomes) for different genders for how we determine whether an individual is a good faith or a bad faith actor doesn't align with the principles of egalitarianism.