I’d argue that the people who think Socialism can only work with abundance, even Communism, fail to understand that Socialism and Communism must be built over a long time, and imagine concepts like “from each according to his ability, to each according to his needs” must be applied to a pre-existing Capitalist economy.

Really, they just don’t see the timescale. There’s no meaningful reason Socialism cannot happen today with current productive forces.