Compare and contrast Nouriel Roubini and Jack Dorsey. The latter is risking millions of dollars on a new Bitcoin service. The former is risking nothing. If Jack is right (and he is) he will help millions of people. Roubini, if he is right or wrong, contributes nothing to society.
This is true of all anti-Bitcoiners, who contribute nothing to society except noise. All Bitcoin entrepreneurs understand that the experience that comes from failure is invaluable and is used in subsequent business models. The Roubinis and majority of US Congressmen don't.