Almost impossible to quantify, though. And I probably read that in something published by a space zealot.
But there have been plenty of benefits. Same with DARPA, but there's been a better return on NASA than from the military budget, I think. It's more focused, and far far less money spent.
Also, I don't think you can say that we should just develop memory foam, or whatever. Many side benefits would never have been looked for without the goal of putting a man on the moon, etc.
Agree on your observation about the benefits of inspiration.
Invaluable, and always under-appreciated by the number crunchers.