Looking to myself I think teen pregnancy would be a horrible idea. How would I pay for it? How would I raise them? How would I deal with a wife 24/7? I'm not nearly adult enough for all that.
But that's exactly the problem she's pointing out, our society delays maturity, prolongues adolescence, so that our lifestyles at given ages are out of synch with our physical maturity. This causes people to ask "why did God make me feel this way if I have to wait until I'm 30 to get married and act on my desires". The problem isn't the design, it's that our society has different priorities.
My parents' generation could live good lives with high school educations. They could finish at 18, and go out and live, and have families. Many did. Many of my professors recounted doing very hard bachelors degrees, having to do a thesis just to get a bachelors. It actually meant something, it had worth because it wasn't so easy anyone could do it. Some people, like those profs still went on to do grad school... but there was much less need. You didn't have to to have a good life.
Today, high school is dumbed down with the "leave no child behind" mentality. It has to lower the bar so that everyone can pass. Education becomes lowest common denominator. The result? A high school degree is worthless. You can't have a life with just that, you have to go do university or collage, so the minimum standard for maturity is delayed another 4 years over previous generations, and not because we're more educated, but because we've lowered standards, devalued education so that more is needed. Then, because you have to have a university education to do anything now a days, those who in pervious generations would have wanted to do a university degree because it suited them, today have to go on and do graduate school because their undergraduate degrees were so watered down so that all the people who need to do them to do jobs that previously could have been done with a high school diploma can still get through.
It's not that we should give up on education and all be ignorant so we can have children young. It's that if we made education challenging again and accepted that not everyone is cut out to have the same amount of education, stopped watering it down so we don't hurt people's feelings, then we could be as educated as we are today years younger, and there would be much less frustration from having to put off our natural and healthy desires until far too late in live.
And we are putting it off too late. 1/3 of couples now have fertility issues because we expect to have children at 35, because that's when it fits in with our society's expectation for establishing careers for a few years after excessive school (to learn very little, just to get the degrees to get jobs), before having kids.
We complain that we have desire too young, we ask, "why did God make me feel this way when I can't act on it", and then we ask, "why God, now that it's finally time for me to have a baby, am I having so much trouble?" We blame God because His design for our lives doesn't match with the society we've constructed, instead of asking why we've constructed a society that is so out of step with how we are clearly designed.
I'm not saying we should get married at 14. But if you look at the number of people who successfully wait until marriage at 18 or 22 or whenever, compared to the number of people who successfully wait until marriage at 32 or 35... There's a limit on how long people can delay our healthy and normal desires. We don't respect that in our society. It can be solved by decreasing consumerism, accepting giving up all the toys we love to be able to have kids younger, and by raising the bar on education, so that it doesn't take until 30 to be grown up, and ready to enter the world as an adult.