I think this might just be age. I have kids but I’m in my mid 20s and still feel very intellectually driven.
Honestly, having kids seems to focus people and help them drive toward efficiency and priorities.
I think some people just slow down more than others when they age.
Alternatively, their priorities might simply be revealed by their preferences and energy allocation. Like the people who want to be very physically fit, but when it’s time to work out they can’t find the motivation.
Speaking of fitness, 40s is when lifestyle and health choices start to catch up to people. The cumulative impact of diet, sleep, exercise, and choices like alcohol consumption start to appear in the 40s or even 30s. There was a stark split among my friends in the 30s where those of us who stayed fit and had even moderately healthy diet, sleep, and lifestyle diverged from those who ate whatever they wanted, didn’t exercise, or even frequently drank alcohol. Claiming a lack of energy due to age (or blaming family, career, kids, etc) was the first major divergence.
I felt an urgency when I was younger that isn't there any more (while ironically being acutely aware I have less time).
I don't know if that is age, or that I feel more content with family life and so feel less need to chase other things, but it's a distinct difference.
If you're not interested, don't have them. I had one parent that enjoyed parenting and one that did not, and having a parent that doesn't want or like kids is so obvious to the kid. It definitely causes issues.
I have found that people don't know what to do with people who don't follow 'the life path', whatever path that is. Like here, I'm an oddball for not going all in on my career or caring that much. In general life, being an unmarried woman with no kids in my late 30s means people don't know where to 'put' you. A lot of parents in particular tend to think of childless people as children/adolescents, which is rather annoying.
One reason I don't seriously seek partnership is that I don't want to give up my time for intellectual and creative pursuits. The usual come back is 'if you find the right person...' but I can't move out of my state without losing healthcare and as a homosexual I've got a small dating pool. Partnering would require compromise on this, and I don't want to.
> Definitely already observe the being seen as children thing.
I'm hoping this gets better as I age. I have noticed people in their early to mid 30s, particularly those following 'the' life path, can get on a really high horse. But the longer people live, the more likely something is to happen to prove to them how fickle and random life is. (e.g. a child dying, a divorce, struggling with infertility, cancer, etc.)