Ah, but I wasn't talking only about startups.
NASA has received something like $800 billion in funding in current dollars. I suspect you would agree that, if that sum had been left in the private sector, some interesting and innovative things would have come of it. Obviously we can disagree about the amount.
There's also the separate argument that lavishing so much funding and authority on NASA allowed it to squash the private space industry for many decades, setting humanity back many years. This was the case until fairly recently, when the 1998 Commercial Space Act helped to change this.
Here's an article I wrote in 2007 about NASA. Unfortunately the original appears to have disappeared in a CNET site redesign last month but (sigh) FreeRepublic copied and pasted it here:
http://www.freerepublic.com/focus/news/1908035/posts
Space, by contrast, until recently has remained the domain of NASA. Burt Rutan, the aerospace engineer famous for building a suborbital rocket plane that won the Ansari X Prize, believes NASA is crowding out private efforts. "Taxpayer-funded NASA should only fund research and not development," Rutan said during a recent panel discussion at the California Institute of Technology. "When you spend hundreds of billions of dollars to build a manned spacecraft, you're...dumbing down a generation of new, young engineers (by saying), 'No, you can't take new approaches, you have to use this old technology.'"
Also remember that government bureaucracies aren't exactly known for their careful use of funds. The Space Shuttle concept was pitched to the public as costing only $5 million a flight; it ended up costing $1.3 billion a flight, with a 1-in-50 chance of disaster upon each launch.