Unironically, the South Park episode on Bebe's boobs is the most simple way to explain this to people.

A girl literally exists (in this case, they notice her "as a girl" for the first time) and every single guy devolves into a caveman vying for physical supremacy because they instinctually know it'll let them touch boobs. They don't even realize it has happened to them, they just change by the possibility.

No matter what a girl does period, any group will be changed by her presence into a hierarchy.

Heck, you don't even need a group to understand this phenomenon. Watch how you interact with a 6/10 girl normally, and then go get off 1-2 times and see how little of a fuck you give about her existence or any bullshit she brings forward. We can't even recognize the level testosterone and other hormones are subconsciously controlling us until the brief respite we have when they are drained.

Which means, absent of any intents by the girls themselves (and they are never innocent in this equation), their existence will ruin any group or focus a man can have to become about her one way or another.