Keynesians have not been in charge in the Obama administration. Everything that administration has done has been less than half-hearted. Better Keynesians would have plowed the money into Main Street, not Wall Street. That said, I'm not a Keynesian.
It would have been easy to stop the foreclosures and all the unemployment though by nationalizing the Federal Reserve, declaring all Federal Notes to be interest-free United States Notes, paying off the National Debt with such notes, and pegging all new issuance to real productivity so that there would no longer be inflation or deflation.
The problem came from the banksters, and the banksters never lost charge. The Obama administration is run by the banksters. There's no doubt about it. They don't want regulations to work. They do everything they can to sabotage them. Their man, Henry Paulson, lied through his teeth about everything so that the banksters would not be held to account, which they have not been.
The Keynesians would never have allowed the fractional reserve system to go unchecked the way it did. Keynesians argued against Alan Greenspan, Phil Gramm, Larry Summers, Robert Rubin, and the others. All the deregulation with all the new, exotic derivatives sank the economy. The Keynesians had nothing to do with any of it, and they haven't been asked to join the Obama administration at all.
I find the arguments in that article superficial at best.