The same reason PSS went moderated on their forums: constant pointless complaints about everything and anything, plus some people loudly DEMANDING things be implemented just for them RIGHT NOW!!!!! (often in all capitals of course to get the point across).
They got sick of having to spend more time moderating their forum than creating aircraft (which is what they want to do and are good at) so they closed it down.
As usual the majority suffers because of a few.
I wish I were flying