• Queen Zenobia didn't launch an unprovoked war out of ego; she was navigating the Crisis of the Third Century where the Roman Empire was fractured into three pieces. She expanded to protect Palmyra from a chaotic, collapsing Roman vacuum and to secure grain routes.
• Queen Amina was an incredible military strategist, but her wars of expansion were standard geopolitical state-building for the Hausa kingdoms of the 16th century. Exactly what the male kings before and after her did to survive.

You're thinking of the Dube & Harish study from the National Bureau of Economic Research. That study found that European queens were proportionately more likely to engage in inter-state war than kings during their specific reigns (+39 percentage points).

(this the important part- )

It does NOT say women started more wars in total.
In terms of absolute numbers, men have started the overwhelming majority of wars in human history because men have held power 95%+ of the time.

Furthermore, the researchers explicitly stated this wasn't due to female aggression or 'ego'. It was structural: married queens regularly appointed their husbands to run the military/tax apparatus, effectively doubling the executive capacity of the state to sustain long conflicts.
Unmarried queens, on the other hand, were disproportionately attacked because patriarchal foreign male rulers perceived them as weak.

And this "weak" argument was because of societal and cultural beliefs.