I've also noticed that and here is a theory which isn't rosy, but maybe there is some truth:
In an area which has little testable results and which is technical/geeky, there is a lot of polarization. People religiously feel they are right and discredit other opinions.
While there are just as many ill-posed questions in other forums, they don't seem to be downvoted so much as on stackprogrammers. Questions which are perfectly fine (or are even favourited and upvoted a lot later) are downvoted, because some people read the headline only and feel the urge to proof others wrong.
I've seen a similar effect in science. Where results are not conclusive, "experts" start fighting for their own theory and write nasty emails to each other. This can happen because none if them can be proven wrong, but stricly no-one is right either. Really clever experts are absolutely convinced of completely opposing ideas given the same data set.
On stackoverflow you write code, which fails if you get it wrong. On stackprogrammers it's opinions.
To sum up:
Untestability + Geek = Discreditation spiral