Sure, but that’s one of many factors to consider. Are the improved chances of healthy kids really worth it if it comes at greatly elevated risk of financial duress, where all that extra energy is spent working multiple jobs to keep a roof over everybody’s heads? Is it worth the risk of divorce when you or your spouse get a better feel for yourselves in your late 20s and figure out you’re not actually that well suited for each other?

I’m sure that there are individuals who have all that sorted before their mid-20s, but that’s anything but a rule and nobody should feel pressured to make the leap at that age.

Yeah but the people who have kids in their early 20s are largely not people who worry about having life all figured out. They are more go with the flow types. There's something to be said for it. The best intended plans do not survive first contact with reality.

I agree that plans rarely work out, but this isn’t about planning nearly as much as it is about avoiding worst case outcomes and unnecessary struggle, which getting started later is generally conducive to (divorce rates in couples married in their late 20s/early 30s are lower than those who were wed in their early to mid 20s, as an example).