OK, regarding point 1: people usually only try this with young women around when they have been experiencing peak socialization pressures regarding personal beauty. Puberty is generally a pretty unpleasant process for girls (no intended comparison vis a vis young men. I really wouldn't know). Certainly some/many laugh it off. Others find it a painful part of the socialization process.
For point 2: Repeatedly signalling to young women as a whole that they only have value when they comply has a psychological impact. At least when I was young, the likelihood that a young woman would be complimented for *anything* other than her beauty was not high. It was very typical that in science classes male students and teachers would just pretend I wasn't talking.
I still remember that guy who went on a shooting rampage at UC Santa Barbara, targeting young, beautiful women because he felt he couldn't get any to date him. He killed a number. Despite *definitely* not being in his target audience, I still feel less safe because of what he did and think twice before rejecting men's advances. He accomplished his goal of communicating, to female-perceived people in general, their social value and possible risks to saying "no."
OK, elaborating on point 2 via analogy. I was once eating dinner in college in my dorm at a mostly male table. This table had repeatedly told me things like I "didn't count as a woman" (which, ok, for me that was honestly both infuriating and kind of thrilling), which gave them tacit permission to say nasty things "with no women around." A long conversation on under which circumstances it was OK to continue sex despite a woman withdrawing her consent ensued. The consensus was that if penetration had been achieved, there was no requirement to stop.
Now, these were my only "friends." I was being bullied by my roommate for being queer at the time and sexually harassed by a couple of female students in the dorm (yeah, I know) and I felt less ashamed of being called flat-assed than I did of being bullied by my own roommate. I wasn't out and had a virulently homophobic family, so I felt that participating in being the target of misogyny could protect me in some way. Plus, they ran the local in-person mafia game and board game groups, and I was shy and wanted to do nerdy things like that instead of participating in the other "in" thing in this dorm, drinking until ill.
These statements broadcast a message: maybe, "don't initiate sex with these men," maybe possession over women in general, maybe "this treatment is the cost of our tolerating you," maybe "if you are harmed, you should know not to come to us."
I wanna be clear that I don't believe most men are like this, but I've also had so many bad experiences at this point with "nice guys" that it's not correct to treat this particular group as statistically insignificant outliers. It definitely wasn't this one conversation, and it wasn't just me. They had a pattern.
Anyway, I don't have any contact with them anymore. I don't know if all this has clarified anything. Note that these are kind of extreme examples which I cherry-picked to try to explain the structure of how this kind of interaction works, not to imply they're of the same magnitude as what you were talking about.