Turns out that's mediated by the sexual impulse, and can be short-circuited via contraception.

It's not that easy to beat evolution, some will still have kids while those who only care about the fun will die out.

No need to wait: they've already fried themselves out of the evolution game with STDs. Any child they have will likely be retarded or diseased in some way.

Don't forget to include alcohol as a drug - "fetal alcohol spectrum disorders", FASDs, are a real thing.

Third such comment I see in this thread. And... so what? What does the Darwinian purpose have to do with anything mentioned here?

Choosing to not have children appears to "swim against the current" of the dominant biological process/context by which one came to be and in which one exists.

Certainly not having children allows one more time to pursue other matters. Mankind in general might gain (or lose) from such behavior, depending on whether one is an Einstein or a Stalin for example. Most anyone who participates in society has some set of interests and pursuit of those interests is nonetheless very real and the results may dominate our perspective.

I see no clear way to judge whether a person contributes more through his/her work or through his/her children. Nor do I think "contributing" (whatever that means) is a known evaluation anyway. And what one man considers useful another might judge detrimental. All the more b/c history is "unfinished business". IMO in summary we simply cannot know.

Aside: there's a T-shirt that shows the sinking bow of a shipwreck through a telescope lens. It's labeled thusly: "MISTAKES - It could be that the purpose of your life is only to serve as a warning to others." Yet another viewpoint.