Have you ever seen teenage boys? A lot of them are basically quasi-feral owing to the newly elevated levels of testosterone unleashed on their brains which are still a long way from being fully baked.
I don't know that "girls" remains the gold standard so much as girls are more able to conform to broader behavioral expectations. This is not to say teenage girls are immune from hormonal-driven behavior issues, but it manifests in different ways. I have a 13-yo daughter and let me tell you it's no walk in the park. But it's absolutely not a surprise to me that boys account for the majority of problematic behavior.
This sounds right. It's not like girls are being deemed "the gold standard." Instead, there's an existing set of behavioral expectations, as you put it, and girls (for whatever reasons) just happen to have an easier time conforming to these expectations.
If societal expectations are things like: kindness, respect, agreeableness, calmness, paying attention, not talking back, not fighting, and so on... and girls tend to conform to these while boys tend not to, that doesn't necessarily indicate a conspiracy against boys.