Denial? When I was a teenager, I watched other boys and men sexually harass girls at random all the time. I mostly mean wolf whistles, cat calls and other uninvited verbal harassment, but I also mean uninvited touching, near-touching and other physical harassment.

I don't think anybody really is unaware of that kind of thing, whether they claim they're unaware of it or not.

In fact, "protect your sister" was and remains a value that boys internalize as noble.

Protect from what?

From the same behavior I described above that some men claim they don't see.

Well, if it weren't happening, if the harassing behavior weren't pervasive, why is the "protect your sister" value so pervasive?

Men and boys DO see sexual harassment. They even mostly disapprove of it when it happens to a girl in their family. Then many of them go do it to a girl in somebody else's family.

Open harassment may be less common today than when I was a teenager, but men who claim it doesn't happen are, in my opinion, consciously and dishonestly denying a phenomenon they very know is real.