I'm not assuming doom. I'm assuming continued decline in the material wealth of the vast bulk of people in America and Canada, following the same four-decade historical trend that you assume can be reversed by relying on inheritances from Boomers and a job market that actually pays well for the average person. I am also assuming that the trend towards greater wealth polarization continues, for at least as long as the Boomers stay alive.
Basically what is happening is that you are being a pie-in-the-sky, drugged-up, hallucinating optimist, ignoring dozens of trends that argue against your point, while accusing other people of being gloomy, even though all I'm doing is pointing to the historical record and known, present-day trends.