You may have something there with the general atmosphere of the forum. But I don't agree that "the most common forumites are Gamma." The plurality is Beta, and this is possibly even more true now than it used to be. We see a consistent pattern of intuitive types, and more often Ti valuers, being the predominant demographic in socionics forums, with a smattering of other types. Some Delta NFs, some SEIs, some Gamma NTs (less than you might expect), some Se egos (more than you might expect), hardly any LSEs, ESEs, or SLIs.