The studies do show that having children is inversely related to happiness, but many people choose to have children anyways since they get a different sort of satisfaction from having children.

A major flaw that seems to run fairly consistently through these studies is that they aren't longitudinal over the course of an entire lifetime. That is, they focus entirely on the effect on happiness of having children while they are children, and ignore the possible difference in happiness when the parents are elderly. The old person surrounded by children and grandchildren is quite plausibly going be happier than the increasingly isolated person watching their friends die off one by one in the relatively unappealing environment of an assisted living facility.

I was never brought up in a loving or close family (asian parents), so I don't really see any benefits to having a family

The conclusion does not follow from the premise. This seems like excellent reasoning for employing different parenting strategies and family values than you experienced in your childhood, not evidence that there is no benefit to family under any circumstances.

I agree with the other comment makers that there are more effective ways of contributing to the world (i.e., saving the world) than causing a few 18-years-olds to exist in a couple of decades that would otherwise not have existed. However (and this has not been mentioned here yet) it might be the case that the experience of having children drastically improves a person's ability to pursue these more effective ways.

(Since most civlizational progress consists of significant contributions from a relatively small number of people, it would be nice if someone did a study of the rate of parenthood in that relatively small group of people.)

Particularly, having children might make a person much better at mentoring than anything else the person might do to get better at mentoring -- including getting practice at mentoring. (I know that many of my readers will consider that unlikely, so I am now going to try to defend it.)

For the purposes of this comment, let us define "mentoring" as the loaning of one's own instrumental rationality to another person to help that person with his career or his life. One advantage of defining the term this way is that it tends to illuminate what I consider the primary barrier to becoming a good mentor: actually caring about the other person approximately as much as one cares about oneself. In other words, the most important fact I know about mentoring is that most who want to be mentors or who consider themselves mentors are vastly better at optimizing their own careers and lives than they are at helping other human beings optimize their careers and lives. In other words, most prospective mentors are very bad at transferring (or "loaning") whatever skills and bodies of knowledge the prospective mentors have for dealing with the messy, not-easily-codified parts of work, life and human relationships.

The evidence I have that parenting makes you better at mentoring is not particularly strong. One big piece of evidence is that many parents seem to love their children more than they love themselves. E.g., when faced with resource constraints, they choose to spend resources on their child's education or health care instead of equally pressing needs of their own. Loving someone more than one loves oneself is very rare outside of the parent-child relationship.

It stands to reason that the hardest part of becoming a good mentor is achieving that first mentoring relationship in which the degree to which the new mentor actually cares about the protege is a signficant fraction of the degree to which the new mentor cares about him- or herself. Having children strikes me as the "royal road" (the most direct path, the best way) to achieving that first successful mentoring relationship. The other royal road would be having a committed sexual partner.

On the other hand, one of the best mentors I have ever met is a woman under 30 who has never been married and never had children. Both of her parents worked in occupations in which mentoring was the whole point. Overall, having parents who are good at mentoring is the strongest predictor I can think of of who will become a good mentor.

Another piece of evidence: I spend a lot of time trying to figure out how to pick doctors because I have had a chronic illness my entire adult life. I am 50 now. Doctors very wildly in how useful they are to their patients, and the doctors who treated me who have children have been drastically more helpful to me than the ones without children.

If you're pretty sure that your comparative advantage is in discovering new scientific laws and such, then the expected utility of having kids is lower because there are plenty of examples (e.g., Newton, Thomson) -- even from the era before effective birth control during which most successful men had children -- of successful scientists never getting married and never having children. Of course, one does not need to be a good mentor to discover a new scientific law (although being a good mentor is a nice-to-have for its usefulness in helping one enter into mutually beneficial relationships with other good scientist-mentors).

If you're mainly interested in optimizing your influence on the world / future generations, things like writing, mentoring and so on are surely much more efficient than parenting.