In the nicest possible way, this is basically the oldest lesson there is. You weren’t happy because you optimized your feelings or had the right opinions. You were happy because you stopped focusing on yourself and became responsible for other people. Six kids needed you, in the real world, every week. That kind of outward focus kills emptiness fast. Chasing happiness, moral righteousness, or political engagement jus…
I'm child-free by choice, so I can only offer the CF perspective. If you're a parent who wants to better understand our viewpoint, or if you're not a parent but are on the fence about kids, I recommend reading "Childfree by Choice" by Dr. Amy Blackstone. It's an extremely comprehensive book that deeply explores why we choose this life and how we find fulfillment beyond the material benefits that come with this decision.
(I want to be clear: There are loads of happy and very fulfilled parents out there, and it is possible to have a rich life with kids!)