And yet, we still need to parse the effects of biology and the effects of situation. Sex differences across species vary based on the various incentives they experience. Sex itself arose out of a need for multicellular organisms to iterate more quickly. In less extreme and volatile conditions, asexual reproduction makes more sense. In certain organisms, all members contribute both male and female gametes, while others have individual organisms specialize in one or the other. It all depends on their specific challenges, modulating to changes in context.

When we think about why men might have advantages over women at the heads of large organizations, we'd have to look more at the context of what is adaptable in those empires. How much of it is due to biological advantages, and how much of it is due to the same self reinforcing mechanisms that favor pale skin over darker skin? The effect of skin color is totally cultural, yet the disparities between darker and lighter skin are compared gender in several places.

There are about 121 non white US House Representatives and 128 women. Assuming a 50/50ish gender breakdown, the disparity for race would be 13% while the disparity for gender would about 21%. In the US Senate, there are 12 non white people and 25 women, meaning racial minorities are underrepresented by about 29%, and women by 25%. For CEOs, women are underrepresented by about 18.5%, and racial minorities by about 17%. If race, a completely cultural factor, has such a similar effect to gender(equivalent to sex for most of these cases), what does that say about the effect gender or sex might have on someone's ability to have positions of power?

Male and female bodies are different, but how much of an effect do those differences actually have on the behavior of domination? How much of the difference comes from gender as social construct, and how much of it comes from the realities of our bodies? Men can usually lift heavier things and women often have to give birth. Men are more likely to die in battle, women in childbirth. People who identify as male prefer to think and act differently than I do, but it's unknown how exactly those predispositions shape our outcomes because there's a mountain of culture woven into every part of those differences. Male behavior is part of human behavior, regardless of how much more often they do it.

Masculinity is but one part of fascism, not the core reason or mechanism behind it. It's just an important identity to manipulate for fascists looking to wield power. The will to power above everything else is at the root of fascism, and the basic will to power is just a fundamental adaptation for all life. If you want an evolutionary explanation, that's it. Seeking power is near universal for all organisms, as power allows them to continue their existence. Those that don't seek enough resources and control to continue simply don't continue. However, all drives can be counterproductive in certain ways, getting culled into homeostasis eventually.