No, I lie. On an intellectual level I do understand, in my usual way of seeing every viewpoint at once, at least some of these things. No reason, of course. But I'll still rant about it. I don't see anything inherently contradictory in defending people's right to write whatever they like, and upholding my own right to criticize it at the same time.
Freedom of speech is a lovely thing.
There's peculiar characterization, and then there's what I think of as no characterization, or the 'wouldn't these two guys be hot together' type of story. This is fairly prevalent in crossovers, especially improbable crossovers. Two sexy characters break free of the constraints of their particular universes and get it on for no particular reason. Actually a lot of PWP's can be categorized as 'no characterization' stories, given the usual range of dialogue during sex scenes. Add names to taste.