> we have immense wealth, medicine, etc. that doesn’t necessarily imply we are psychologically healthier or happier.
That may make sense if you compare us to a few generations ago because maybe we're almost in a "diminishing returns" phase and our lives aren't significantly better than our closest ancestors. Nevertheless, I'm not sure if we were happier during periods of famine, plague and inquisition. It is still possible to have a "go-to oversimplified answer to this" even for this "go-to oversimplified answer to this".