Antinatalism, in my eyes, can be reduced down to only two major statements, the second of which is taken as a logical consequence, whether wished for or not, of the first. I say now that a good amount of people will not accept the first of these, most likely because of their religious beliefs, and others may not be swayed one way or another as to whether they accept it or not as they do not much care for other human beings (psychopaths, for example). But upon their reflection, I sincerely think - or else my view of humanity must descend even deeper - that the majority of non-religious (or not strongly religious) people on this planet would accept the first proposition, and in doing so will only have to swallow another half of the red pill that is antinatalism.
The beliefs core to antinatalism are:
1. The ultimate goal of humanity should be the reduction of suffering (just as the personal goals of most people all boil down to the reduction of their own, or of their loved ones' suffering)
2. As a result of 1., people should not breed.
Of course, one could quite easily claim that I'm making an arbitrary division of thought here - I could quite have easily, you say, divided antinatalism up into 3 or 4 separate parts, and said that most people are 1/4 of the way there, or 1/5 of the way there, etc. But that isn't the point, I don't think. The point is, there isn't THAT much cognitive distance between antinatalism and the common person's thoughts. Or the cognitive distance between antinatalism and an ordinary person's mindset isn't as large as you might think. Once you have someone realise that they would prefer a world with less or no suffering, then it SHOULD be easier to convince them that a logical consequence of their original belief is the negation of their genes' conniving and scheming to produce more and more suffering. Of course, hypothesis doesn't determine what happens in reality, reality determines what you do with your hypothesis. And in my arguments with people, I'm not so sure that it is significantly easier to get my point across when I have convinced other people that the primary goal of human existence is to end suffering, though it does certainly sound as if that would help.
In other news, someone on an atheist chatroom recently told me that VHEMT has a humorous section debunking reasons why people think they should breed. Check it out, here.