Whenever I see something that occurs often in a particular case, I'm going to generalize it. I do it because its easy and I don't get offended or annoyed when people stereotype me. Whenever I, personally, make a generalization, I'm not talking about the "Exceptions." I'm poking fun at the fact that it SEEMS like everyone is like this.
So, yeah, it SEEMS like the F's are sensitive to a lot of things - the word doesn't get around for no reason. As long as someone isn't really being derogatory, such as saying "Ugh you stupid INFP" or something to that affect, I never got why it was such a big deal.
Just throwing my cents in to see if anyone else agrees.