I think that's just a sort of rhetorical decay of the argument that their general standard of living and wealth is built on imperialism just like it is for the rest of the imperial core, regardless of the localized victories their labor movement has won, like someone hears that and then in the repeating of it "quality of life" becomes conflated with and replaced by the welfare state specifically.

It's clearly a response to how liberals tend to point at the wealthy scandinavian countries and try to declare them "real" socialism because of the comparatively high wealth their working class enjoys, which is an extremely toxic rhetorical trick that's done incalculable damage - it was even ostensibly part of fucking Gorbachev's reasoning in his hairbrained plan to do scandinavian social democracy from the left, not understanding that much of the western wealth came from imperial exploitation and that the USSR's base of productive capital couldn't maintain a tolerable standard of living for everyone (thanks to Khrushchev-era reductions in production of industrial capital and the refocusing of the economy onto consumer goods) if inequality was allowed to grow through liberalizing reforms and some people ended up with much more than others, and instead required constant load balancing to ensure there was enough for everyone (and of course liberalization did far worse than merely leading to unequal distribution of scarce goods, it also led to the cannibalization of productive capital by private enterprises and complete economic collapse).