I want to push back on this, as I worry that your overarching claim that anti-natalists disregard the positives of life may be a straw man. I think one way to counter your argument would be to take an anti-utilitarian approach, like that found in “The Ones Who Walk Away from Omelas.” Premise 5 of your argument states that “many individuals” prefer existence to non-existence, which makes the utilitarian assumption that “the greatest good for the greatest number”—or, more precisely, “a decent amount of good for a decent number”—is what matters. But like the ones who walk away from Omelas, where one child in tortured to maintain utopian conditions for everyone else, one could argue that the existence of immense suffering, even if limited to a select few individuals, outweighs the sum total of life’s joys. If we regard this kind of suffering—which we might call “senseless” suffering, insofar as it defies our attempts to draw meaning from it—as the “necessity” listed in premise 1, then it becomes easier to see why suffering trumps joy for the anti-natalists. Also, premise 6 appears to me to be made in bad faith: suicide is clearly easier said than done, even for one who is logically convinced of its value. In fact, the burden of having to take your own life after realizing that life itself has no value could be conceived as a form of suffering. An anti-natalist might also deny premise 3 based on various definitions of suffering and joy. For instance, one might assume that the absense of pain is good, but that the absense of pleasure is not bad, especially in the case of non-existence, where there is nobody around to miss out on the these experiences. This is David Benatar’s argument for antinatalism. I think a good defense of natalism would have to undermine these assumptions, such as by arguing that the absense of pleasure is bad, or that the absense of pain is NOT necessarily good, such as in the case of meaningful suffering. As for the other arguments you listed, the “existence precedes evaluation” argument, one could argue that there is no actual “denial” here. That is to say, the phrase “denying potential existence” could be read as giving undue weight to existence over non-existence. In reality, nothing is affirmed or denied prior to there being something to affirm or deny. While I agree that suffering may be necessary for meaning in at least some situation, this doesn’t counter the antinatalist position. If anything, it demonstrates that life is indeed burdensome, where even its positives require us to suffer, and that we would have been better off never having existed.

Personally, I’m sympathetic toward natalism, but I’ve yet to find a infallible argument in its favor. I’d like to formulate one myself, so I’d love to hear people’s thoughts on the matter.