I hate it when I'm expected to conform to a stereotype rather than treated as an individual. I really hate it when people say "women are like this" and then expect every single woman to be more or less like that.
Ge me right here: I know that we are all prejudiced -- that we all have a tendency to have expectations based on previous experience. I also know that when it comes to problems in inequality between groups, it makes sense to discuss those differences. The problem is when people are unaware of their assumptions and think that their experience of how things are on average is a prescription for how things should be. That's when they (mostly without knowing it) put pressure on others to conform, rather than to try and meet them as the individuals they are.
Oh yes, this is a pet peeve. And very personal.
Let me give some examples.
I (call me A) once talked to a female colleague (let me call her B) about a woman we both were acquainted with (C). I was a little bit pleased with myself for having deduced that C was practicing some martial art from her relaxed stance when we had to stand and wait for a long time. I know that in that way you can stand forever without getting tired, and you are balanced and prepared to go. To explain what I meant I imitated it (probably not very well) to B. Her reaction: "That's not a very feminine way to stand".
You might see this as a very innocent comment, but what it tells me is that B judges (including C) people from her stereotypes, and the most important thing about how a woman behaves is whether it's feminine. By repeating comments like this she tells me (and everyone around her) that even if she doesn't say it, she thinks I should also first and formost be feminine as much as I can help it, before I can have any other characteristics.
This makes me a bit angry, but I'm too polite to always thake a fight. I hate those little innocent comments, because they are ultimately opressive. They tell people: stay in your place, behave as you are expected.
I know that there are many differences between men-on-average and women-on-average, but I also know that those differences are smaller than the variations between individuals. I think it should be expected of everyone in a polite society to at least have the ideal to allow others to be different from the stereotypes. I think that it's difficult to get to know people as fascinating persons if you always see them through your normative ideas. And sometimes I think it's worse for men, because they often have even more pressure on them to be male.
When I hear the men in the coffee room talk about their wives as "the boss", and exchange cliche phrases of how women are of course incomprehensible to men, I almost feel sick. What does that mean for how they see me as a professional? I might be oversensitive, but on the other hand this actually might have consequences for how people treat each other. If they expect communication failure, I would not exactly be surprised if they will have communication failure. And they spread this expectation, giving it on to others.
By the way: I mentioned exactly this coffee lounge incident to some students over lunch one day. The reaction from the male student: "What, are you a feminist?"
"I'm a woman, isn't that enough?" was my answer.
I don't want to be a "real woman". I want to be me. And I don't want the first reaction when I speak about something I find interesting to be "isn't it very unusual for a woman to be interested in that?" (Maybe more about this another day.)