Of the people that lived 100K years ago, we have almost nothing. Possibly some cave paintings, though the vast majority of art from then must be gone. However, every single person alive today is descended from people who lived then. You may or may not find that meaningful, but it would be hard to disagree that having children was the most impactful course of action available to anyone alive then. The same is true for nearly all of human existence.
With the current pace of change, having children may no longer be the obvious winner it has been for all of history, but it might still be...
Fossilised remains in the sediments on earth are all that remain of the species that have come and gone before us. Many species are lost to time, because they weren't fossilised or their effects preserved. And our fossilised remains will be lost to the cosmos as well. You experiencing humanity in the midst of it might make it seem substantial. But we are a genus a mere 2 million years old and a species as young as 200000 years. For comparison, the dinosaurs roamed the earth for 165 million years. All of human history is 200000 years, again seems of consequence to us because we are participants in it but on the grand scale really isn't.
Does that mean we shouldn't just bother, absolutely not, we are given this gift of experiencing life. Something rather than nothingness...etc. But we can do with a little more perspective on how utterly inconsequential we are in the grand scheme of things. Having kids seems consequential in the context of human existence, but when human existence is inconsequential (there is no lasting impact or transmission of information beyond our temporary side-effects on the environment) it puts our existence into perspective.
With the current pace of change, having children may no longer be the obvious winner it has been for all of history, but it might still be...