Despite his impressive pedigree, Paul Krugman is more of a political mouthpiece than an economist. His regular opinion pieces in the New York times or frequently abrasive and wrong.
It's possible that growth would have been even more anaemic without the internet, but that's hard to argue from the data.
On team academia, Linus Pauling, Edward Teller, Bertrand Russell, Paul Krugman, etc. On team Hollywood, Jane Fonda, Clint Eastwood, Al Franken, Madonna, etc. Being tremendously prominent in one domain has only a loose correlation with expertise in something else quite different.
That's easy to say if all you read are his opinion pieces rather than his academic work.