ARPANET: Really the Internet Heroes We Make Them Out to Be?

I found this video of Ward Christensen, who co-created the first BBS system, talking about his time with ARPANET, and how he lent them the ideas he found on his own when they weren't getting anything done.
ARPANET was a Department of Defense project which is credited with the creation of the underpinnings of our modern internet. Libertarians often have to take a hit on this, as it is true that the internet is important and it seems like the government did create it. And to a large part, they did. This serves, in my opinion, as a weak spot in libertarian dogma.
Christensen's interview for the BBS documentary reflects, however, that maybe private innovations helped spur a lumbering, slow-moving project along.