Although feminists do make a lot of absurd arguments, their opponents do occasionally make some too. I have recently seen an argument that look like the following:
It was cross-culturally observed that women were regarded as the inferior gender in ancient times, therefore, it is adaptive to do so. Thus, women are, indeed, the less capable gender.
I doubt this would be a valid argument (but I think it carries some truth). This is because it has a hidden premise, which look like this:
Things that are adaptive in ancient time must also be adaptive nowaday.
Without this premise, this argument won't work. The point is, we know that environment changes. For instance, humans developed a preference for sweet taste in ancient times. However, seeing all the obesity and health problems caused by sugar consumption, I doubt if this instinct is adaptive in nowaday society. Therefore, the hidden premise is NOT true, and the argument is not valid.
As mentioned, I believe that there are something inherently wrong with the female gender, but I don't think the "adaptive" argument is a sound argument. The conclusion may be correct, but it is not valid.