If you had kids earlier, you wouldn't get more time with the specific person you love that is your son, you'd get more time with a different son. No doubt you'd love your counterfactual son too. But you shouldn't feel bad for having done any wrong by your real kid. This is the only timeline he could exist in.
Bit of a thorny philosophical argument, maybe, but reasonable in this case.
Have considered that as well but shared time with that person would have been more and I would be none the wiser to the actual timeline, so I feel it’s appropriate to treat them as the same “child” instead of theoretical kid vs actual kid and how I’m happy I waited because this kid is so cool, pretty sure I would have felt the same towards the other kid (who knows maybe not but even if he was a jerk of a kid I’d assume a delayed child would have also been a jerk too)