Like a lot of the deviations and sexual side streets - S&M, furry cos/play, role playing and other (and there is a huge amount) fetish based stuff with a high sexual content (though often no sex) - most people just don't even want to try to understand it.
On top of that in general, I think the specific trouble with sissy is that it goes to the heart of the deepest and most permanent/historical (and hence most stereotypical) divisions between the genders. Many of the MtFs on here had that word used as a weapon on them, and I think that even some of the FtMs worry if their presentation will be able to pass that threshold so you've got that apprehension aspect to it. On top of that it's a huge sexual fetish deal, and there are a lot of people in here who have a fetish about fetishes (though I'm pretty sure they don't really understand what they are). Plus it's something that is very highly male, in that there is no real born female equivalent to sissy. There is no widespread female sexual fetish for tomboy. So that makes it harder to understand. Then you have the age aspect to it, and for a lot of people - perhaps even a pretty vast majority - age role playing in a sexual context is beyond the pale and hence something they can't - or won't - talk about.
But I kind of like it. Not in the sense that it appeals to me specifically, though from sissy to like 40-50s fashions is not a huge step and has lots of crossover, but just in the knowledge that it's there. They were, some of the first people to really 'find' each other on the net if you trace the rise of net communities, particularly the alt-sex stuff. (Petticoat Pond looks just like it did in 1996, and everything on the net looked like that in '96) And, where some of (OK, a lot of) the S&M&B&D and all that is very scary, there is nothing on the planet less threatening than sissy except perhaps 'bunny' and even rabbits have teeth and bite.
There is part of it that is a clothing fetish, and there is the maid deal, but when you look deeper there is another entire sissy deal has its own subculture of meetings and camps and weekend activities. So its not just the clothing, its heavily involved with actual age appropriate activities - but the maid thing involves lots of activities too. But really I'd rather color between the lines and string beads, and make lanyards than scrub the floor and make dinner. But it's that entire 'world within a world' that interests me.
So it's fine to talk about, it's in the CD section and I'd think its just one more part of that section of the spectrum.