Thanks a lot for this! I am writing my thesis on QE and found this really helpful! He provides much insight about QE and points out the very important issue which is the mismatch between monetary and fiscal policies.
Also, various empirical studies (including my own results) have shown that QE has been effective in lowering the interest rates (at least in England and U.S.A.). I personally think this is enough to show that monetary policy has achieved many of its goals but has been betrayed by a weak fiscal policy, as discussed in your interview.
All in all we have learned a lot since the financial crisis happened. The experience with QE and the importance of realising that it is not enough on its own to stimulate an economy is one of the key things points have learned.