Same.
The only family I know with 4 kids are very religious and don't use contraception, just leave it in the hands of God. They had 3 kids with maybe 2 years between them, then a surprise 4th when the next youngest was 6.
They are a lovely family, both doctors, lots of money, lots of family support.
I don't know any other large families. Most other families have either 1 or 2 kids, very occasionally 3.
I don't know any of these women who have children throughout their 20s, 30s, 40s.
Also, OP, not sure what you are getting at by saying you don't understand people who say you have less time with your kids if you have them late.
I feel you are being disingenuous but I don't know what.
If you live to 80 and have a baby when you are 20, you will have 60 years with your child and they will be 60 when you die.
If you live to 80 and have a child at 40 they will only be 40 when you die. 20 years less time than if you'd had them at 20.
Do you genuinely not understand that?