Samuel Morse did not invent the telegraph, but he made it practical.
Edison, Bell, Ford and the Wright Brothers are famous because they made these things work.
NASA dserves all of the praise it gets on these and many other things.
The opportunity cost concept, used in hindsight, is not very useful.
You could also make the excellent case that if so many bright driven lads of the 1960's were not busy getting Apollo on the way, they would have invented and built a much more dangerous Cold War arsenal.
So maybe the opportunity cost of the Space Race was the continued cold peace......
NASA has been incredibly useful and productive for us.
It may even be that we will figure out just what Mars is made of definitively....
:^)
Ed