Post WW2 was a time of labor scarcity the US benefited from - but eventually that went away with global competition. The tech boom years were another labor scarcity time, and that’s also going away.
Both these times were plausible ways of entering the middle class.
What does economic theory say should happen to labor when scarcity ends but capital is strong? Does the economy expand until there’s more labor demand? Or will structural and monopolistic problems cause capital to benefit while suppressing wages - making us all serfs?
Labor supply and demand do not reliably reflect the productive or social value of labor.
An explanation to your analysis:
"War begins to be presented as the heroic alternative, the last hope, the “way out” from the unending nightmare of economic crisis, misery and unemployment. Fascism, the most complete expression of modern capitalism, glorifies war. The filthy sophism “War means Work” begins to be circulated by the poison agencies of imperialism, and filters down to the masses. ... War is only the continuation and working out of the crisis of capitalism and of the present policies of capitalism. It is inseparable from these, and cannot be treated in isolation. All the policies of capitalist reorganisation, all the policies of Fascism, can only hasten the advance to war. This is equally true of the line of a Roosevelt, a MacDonald or a Hitler. War is no sudden eruption of a new factor from outside, a vaguely future menace to be exorcised by special machinery, but is already in essence implicit in the existing factors, in the existing driving forces and policies of capitalism."
- R.P. Dutt, Fascism and Social Revolution, 1935
Any system based on exponential growth will have almost all people become serfs as even if their capital grows it falls behind the growth of older capital