I read two other typology forums where I am not a member. S-types on these forums have openly said that there is no anti-S bias (and I don't think there is one either!), and yet, on those forums, 95% of the forum are Ns.
Just saying. I honestly do think that Ns are more interested in typology. They are more inclined to learn a theory just for its own sake, as a mental exercise, even if it has no practical benefit (necessarily). Whereas Ss, ime, especially SJs learn the theory because they want to be better parents, colleagues, etc. Not just for its own sake. Of course this is a generalization. I mean by and large, not these specific cases. I also mean no harm, I am an S myself.
ETA: Keep in mind a very small percent of the population actually likes typology in the first place -- and to the extent of joining a forum? It's very, very rare. It would seem that, regardless of type, most Ns and most Ss alike aren't interested in typology. So it's not that "most Ss spend all their time on facebook and don't like internet activities that make them think", it's that most PEOPLE prefer to spend time on social networking sites, or use the internet for a purpose other than what we are doing here. At least, this is what I have seen.