Blyth has the best analysis of the changes the West is undergoing. I recommend the video you linked to everybody.
Democracy is a vote market, and strong identities are the strongest persuasive tool available for acquiring votes. Strong identities we know of are skin color, religion, and universalist ideologies (think communism).
Once a particular identity, or combination of compatible identities becomes large enough to have a chance at becoming a winning coalition, the logic of the democracy market almost guarantees it will be deployed for that purpose. Even in the absence of underlying economic factors.
TLDR; democracy has a lot of very scary failure modes, and the US has been lucky to avoid them because until very recently, there haven't been strong competing identities, so people have been free to argue over tax rates.
But doesn't this Presidential election at least suggest that enough people got unhappy about the very "fixed" (more like steadily declining) economic "resource" known as the working class job to swing the election to Trump?
All the raw statistics, from labor force participation to suicide rate changes, suggest your point isn't correct, except in a theoretical sense, or "any practical sense" except in the very long term.