It sounds like you and I are defining misandry in different ways.

We seem to be in agreement that misandry does indeed stem from the patriarchy. And it would follow that ending patriarchal hegemony would liberate both sexes from misogyny and misandry.

The difference is how the actionable misandrist offenses are directed very specifically against boys and men, in these cases -- custody rights, forced paternity, insurance rates, underreporting of sexual abuse/violence, educational neglect, farcical depictions in pop culture, et. al.

Obviously, there are parallel and divergent ways in which misogyny is so prevalent in the lives of girls and women. You and I probably jointly recognize a majority of them, so there's no need to recap them...since that isn't what you were even disputing, in the first place.

So, yes, patriarchy is the root cause for both misogyny and misandry. But the ways in which misogyny and misandry manifest themselves are different.

Finally, I flat-out reject the core principle from ANYONE that data and statistics uniformly supersede lived experiences.