Your derision seems to be narrowly focused on IQ as a filter for its own sake. But it's not that an IQ filter is valuable as an IQ filter, but that it correlate

Your derision seems to be narrowly focused on IQ as a filter for its own sake. But it's not that an IQ filter is valuable as an IQ filter, but that it correlates with other traits that might be valuable to someone. But filtering is hard. If you agree that a high IQ allows you be good at X, then first filtering for high IQ will get you closer to finding those highly skilled X's. Sure, you can just find people who are good at X directly, but this isn't always easy and its not like connecting with such groups is trivial once found. Being good at X may require a massive upfront investment that not everyone is in a position to expend. Besides, the value of such groups isn't just being connected around some narrow technical/high skill topic, but rather being able to connect with people who have unique and interesting views on a wide range of issues. Just being, say, a contributor to some open source project isn't going to get you that. > Saying something categorically about "modern internet" is like judging the highway system or rail network. The "modern internet" is in contrast to the internet prior to social media where finding intelligent people to discuss various topics was as easy as finding a newsgroup or a forum on the subject. The self-selection effect of the pre-modern internet on the quality of average discourse is hard to overstate.