Extreme anti-natalism is the view espoused by David Benatar according to which "it would be better if there were no more humans" (David Benatar and David Wasserman, Debating Procreation, Oxford UP 2015, 13) from which axiological thesis there follows the deontic conclusion that "all procreation is wrong." (12) A moderate anti-natalist could hold that most procreation is wrong.I assume that it is only human life that such people think has no value. Otherwise they would be opposed to all life. I guess they think it's OK for plants and animals to flourish and multiply. I happen to think that human life does have value. I think it is better to be alive than never to have been. I have often expressed agreement with John Hall Wheelock — "to have lived / Even if once only, once and no more, / Will have been – oh, how truly — worth it."
I suppose those that think otherwise are doing evolution's work by not procreating, since lacking a sense of life's value would seem counterproductive to survival to at least some extent. Why they continue to put up with what they claim is a valueless existence escapes me, as does why they are taken seriously. As Orwell said, “There are some ideas so absurd that only an intellectual could believe them.”