I can think of legitimate reasons I would apply to my own personal life, but ultimately you have to make your own destiny on that one.

In my worldview, financial hardship, an immature spouse, or religious (enlightenment) pursuits are all very legitimate reasons to not have children.

But many people in any one of those positions have kids and it works out great so it’s a very personal journey.

I’ll also note that I understand that all three of the examples I gave are somewhat within your control, so there would have to be a lack of desire to have kids as well. If you lack desire, then you definitely shouldn’t.