Why are you so intent to make that choice on behalf of other parents who have demonstrated to be a good providers to their own kids - trade a little now for more later? How is that any of your business?
There is no proof that what you are suggesting is a good trade. It may work for some but not for others. Look at the Taylor Werner thread for example.
I also fail to see the obsession with the future but maybe I am too French. There is value in living the present. Enjoy today. Plan a little for tomorrow but still enjoy today.
And, no, Grace Ping never opened up to be a high profile case study. She most likely simply enjoyed the moment. I think you self-invited yourself to provide a critical opinion. And you cast a bet that she will fail. In anything we do, any of us are far more likely to fail than succeed. Most runners will never attain what Grace did when she was 14. As a result, most will never be able to use past successes for moral support when they eventually run into personal difficulties later in life. That is what her parents are giving to Grace. It is the self-confidence that she can rise to the occasion just as she once did. Meanwhile, you can preach Patience Grasshopper and suffer. They are teaching her to fight. They are right and I admire them.
How about Nedrow, Vannerson, Puffer or Miller? Anything wrong with them? They have parents and you are not one of them. Take care of your own kids and let other parents take care of theirs. Hopefully one of them will rise to be a great runner in adulthood but if none of them ever do, they are still wonderful kids today. There should be no debate.