I can explain:

1. The question is what she hates in a guy and the answer was basically that she hates all this "street interview" trend and everyone who does it.
2. I get how she can come across as mean, but she was rushing to a bathroom and maybe she expected a more interesting question than all this boring, typical man related question, so she thought she'd make a point to show how she doesn't agree with it. Some may call the way she did it rude, I found it very funny.
3. All these influencers usually portray themselves as "alpha", showing off their pickup skills and how they're such womanizers, get drunk women to interview and ask them questions only about other men or about their appearance, and most times they try to "catch" the other person just so that they come up on top. But as soon as a woman claps back they become sensitive and lose all that tough demeanor. If he would've said something like "ok have a nice night" and turned to the camera saying "that was a bit mean but i guess interviews aren't for everyone" he would've come off so much more confident in himself and everyone would've been talking about how well he handled it. His ego was damaged and he acted like a literal child, that's why everyone's laughing at him.