Some of this makes sense but I think we need to talk to the people who have no money and who are living a life in constant debt to say whether money brings happiness and it depends on our interpretation of happiness. Also it is no good asking just Americans as they are a privileged group in the World and most have never experienced true hardship as we know it so it would take more to make them happy than someone who has never had anything and lived with extreme hardship. We all change our perspectives when we lose someone or something .Having said that I know people who work and live with those in extreme hardship and illness and they simply do not empathise with most of us who live even normal simple lives and are so used to seeing people who are always suffering , so even the bare essences of what we have as usual everyday life..even if in deep debt and hardship, they would consider luxury.
I agree that pain is a memory and many forget that easily but I think it depends on the support you had at the time and other factors. If your general experiences were that you were alone in the pain or it was not supported or acknowledged then it can be much worse a memory than for someone who was treated well and cared for afterwards.
I think it is good that he took time to analyse but for someone in a privileged , exceptionally highly paid profession and lifestyle and possibly private hospital treatment..his experiences would be based on what came out of that