I mean, its the reason the US managed any kind of post-WW2 growth at all. Social Democracy delivered the promises of Fascism without the explicit stink of ethnic nationalism. You got strong unions (for whites) and expansive industry (for whites) and an enormous investment in public education and housing and guaranteed jobs (for whites) and you even got those endless foreign wars that Americans love so much. You just didn't have to worry about a Soviet Army breathing down your neck, because you'd struck a Detente and done a Cold War rather than a Hot one. You could integrate enough of the (newly christened "white") migrants into the fold without tripping over the contradictory economic demands for labor and ideological demands for racial purity.

So you got some of the knock-on benefits of a large professionalized workforce by dramatically expanding the cohort of prospective elites from "handful of ultra-wealthy coastal families" to "anyone who can pass the test".

The horrifying thing about social democracy is that - if you can keep yourself from tripping over your own dick and stumbling back into capitalism->feudalism->slavery again - you can do a compartmentalized socialism and reap enough benefit to stay ahead of the curve internationally. It works in a certain macabre fashion. And it can keep working, so long as you can socially reproduce it.