If you are poor, then having children before 25 birthday is likely better choice. The older you are, the more health problems happen and the more tired you are. In that situation, having children while you are still physically strong and healthy is better idea then waiting till you are over 30, tired and cant afford to pay for higher risks.

These people wont have better paying jobs when they are older. It makes little difference financially.

Perhaps that's the rub? Had those same well-educated, high earning folks pursued procreation instead of education and careers in their formative years, the infertility later in life wouldn't be a concern (and likely more of a blessing).

That sounds like selection bias to me. If you're infertile and uneducated/low earning, then you're not going to be pursuing any IVF options.

The educated and affluent people having few or no kids, while poor teenagers have lots of them, is not a recipe for the long-term success of a nation or society.

Either we make life on Earth sustainable before that or we won't have enough time to develop the technology to settle on Mars anyway, so thinking of Mars as a backup Earth does not seem like a particularly good idea.