In characterizing this trend, it seems as though you are assuming that membership in these various communities is mutually exclusive. However, this doesn't have to be the case. For example, a person may be both a Catholic and a leftist. Thus, a good follow-up question might be: To what extent does leftist politics and Catholicism have an impact on a person's evaluation of risk. For example, one could compare Pope Benedict with Pope Francis, who are both Catholic, with each other and potentially conclude that income inequality/exploitation influences Francis' conceptualization of risk to society to a greater degree than abortion or sexual immorality.
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.