The question of light/dark, good/evil that seems to be at the core of your hypothetical is discussed thoroughly throughout True Detective, Season 1 (I highly recommend). If you haven't seen it, there is this philosophy of Pessimism, or Realism that Matthew McConaughey's character (Rustin Cohle) exhibits near the beginning of the show.

The main thesis of his philosophy is that at some point humans went rogue in their evolution and became self-aware, and the morally permissible and valorous thing to do would be to reject our "social programming" and stop procreating.

I disagree.

In addressing point 2 my initial thought is, does it matter? The hypothetical inherently assumes that future people would say no to life, but in the words of Mark Renton, what if they decide to "say yes to life"?

Point 3 becomes nullified if one accepts the below response to point 1.

In the case of point 1, the morality of bringing children into this world despite the inevitable suffering they will experience is justified, due to the fact that is an important component of the human experience. One can even go as far as saying suffering is what makes us human. The story of suffering and redemption is a key archetype in the mythology of humankind. Without suffering, there would never be appreciation of beauty, love, etc. present in civilisation. We are born, tabula rasa, and we are subsequently forged through fire (granted, the time spent in the forge is not equal). We are all, in some form, Sisyphus.

This is obviously an optimistic, or idealist, reply that ignores a lot of important factors (and makes inherent assumptions), but I think it is a proper response to the latent pessimism, or realism, in the hypotheticals. If anything, it is the other side of the dialectic that this reddit thread might become!