No idea. However I am unaware of any social pressure to join LW. On the other hand, there is a lot of social pressure to, let's say, display environmentalist sensibilities.
Hm. Perhaps I asked poorly.
Would you say the social pressure as motivation to agree with the severity AI risks becomes significant once one voluntarily joins a community like LW?
If there are, say, 1000 active members, 500 of which believe that UFAI is the most important threat to deal with, how many of those 500 people have authentically arrived at that conclusion by doing the math? And how many are simply playing along because of social pressure, status-seeking, and a sort of Pascal's Wager that benefits them nothing for dissenting?
If I were to ask the question "What threat poses the greatest risk to society/humanity?" to several communities I would expect to get some answers that follow a predictable trend:
If I asked the question on an HBD blog I'd probably get one of the answers demographic disaster/dysgenics/immigration.
If I asked the question to a bunch of environmentalists they'd probably say global warming or pollution.
If I asked the question on a leftist blog I might get the answer: growing inequality/exploitation of workers.
If I asked the question to Catholic bishops they might say abortion/sexual immorality.
And if I were to ask the question on LessWrong (which is heavily populated by Computer scientists and programmers) many would respond with unfriendly AI.
One of these groups might be right, I don't know. However I would treat all of their claims with caution.
Edit: This may not be a bad from thing from an instrumental rationality perspective. If you think that the problem you're working on is really important then you're more likely to put a good effort into solving it.