Marriage and children seem less and less pleasurable today, burdened by financial worry, relational problems, and high rates of divorce. Is it worth the pain, given the tarakhē (τᾰραχή) it entails for young men and women?
Raphael Raul Yes, as Cassius said, there are a lot of issues worth discussing in your original post. Not the least one being that Epicurus seemed to discourage creating children within the marriage contract except if you were one of the rare Wise Men. But that is not my main point.
I think the angst, if I can call what you described with that word, is nearly unknown for most of the world's population. The pleasure/avoidance of pain effects involved in childbearing within marriage are not the most basic. Those who desire pleasure, dare I say unnatural and natural/unnecessary ones that are available within western Industrialized educated, rich societies rather than fulfilling some biblical originating duty to procreate are minorities even among that overall group.
Also, the pleasure urge, expressed as sex leading to babies, of the non Industrialized part of the globe, comes from the basic, human (animalistic based desire) to find pleasure in the sex act.
I want to say that sex scratches the urge for pleasure far better than unnatural/unnecessary things. Note that I don't say sex is absolutely necessary, but (fill in the blank) sure is pleasurable and available to anyone in every station in life.
As a fellow senior citizen, I respectfully suggest that concern over population ebb and flow in the future is not worth the time spent on it. It is for those elite in every society who enormously profit from the labor of the populations who need to worry. For me, relief over these issues comes from to the teaching: Do not fear death. In a sense, we should not fear the future that will unfold slowly after we are gone, it means nothing to us. And the kids will do fine.