I don’t think it’s condescending at all. It’s a tough pill to swallow at best. I’m not saying those things are wrong to want or that they have no value, only that doing it as soon as possible will have you miss out on a lot of experiences and opportunities that may not be present after you settle down. Therefore, doing it earlier is not a win, as implied in the original comment.

Edit: This is an example of the classic marshmallow test.

Yes it is an example of the marshmallow test, but not in the way you think. You failed the test, and the people you mock passed it. They are willing to make sacrifices in the present in order to create a better future, while you chase instant gratification.

You’re making a lot of assumptions about me knowing nothing about what I do or will do in the future. For the record, having kids is not a noble deed and does not automatically result in a better future. Overpopulation is a burden on society. Having kids is a mostly selfish act because most people would rather have their own kids than for someone else to have more kids and they have none. Besides, who is going to finally enjoy this better future? Or are we just supposed to perpetually kick the can down the road until climate change kills us all?

If everyone thought like you then there would be no future as humanity would go extinct. It only takes one generation of everyone subscribing to your philosophy to kill us all versus the uncertain future of climate change, where there is no scientific evidence that we will all die. Unfortunately, too many people in the West think like you, which is why overpopulation isn't a problem in the West; in fact, the reverse is and governments are covering it up by increasing immigration. If you're concerned about overpopulation on a global scale, you better be prepared to address it (possibly violently) in Asia and Africa.

Unless you are an Einstein-level genius (who by the way, had kids), the best contribution you can make to society is to have kids. Kids are multipliers as their achievements can not exist if they are not born. There is no "experience" that is worth dooming humanity to extinction, and I also doubt you can name any experience that a parent has not had at some point in their life.

"Flyover country" is very condescending, belittling and arrogant.

What exactly are they missing out on? Perhaps you're missing out on what they have as well?

Telling people what their priorities in life ought to be is absolutely condescending. It's not a marshmallow test. It's a question of personal priorities and values. Looking down on people because they have different priorities and made different choices than you, telling yourself they missed out in doing it, it's really just a way to convince yourself you're happy with your choices and nothing more.