Outside of adoption, this is less applicable to women as their ability to have children begins to rapidly decline after age 35. However, men can still have children at an old age with younger partners. This question also applies to adopting at an older age, but minus
#2 below. My issues with this:
1. Having a child at such an older age effectively deprives the child of having one or more parent around when they grow up. If a 50 year old man has a child, by the time that child graduates college, the father will be around 72, with not much time left on the clock. Compare to parents in their mid 20s when they have that child - they will be somewhere in their mid-late 40s when that child graduates High School, and thus can actually be there for their child as they grow, and participate in ways that a very old person (70+) can't. It is unfair to do this to a child imo.
2. Children born to older parents are a higher risk of being born with defects.
For instance:
Edit: Not saying people
must have a kid in their 20s - in their 30s is also fine.