That sliver of a few decades between, on the one hand, slavery, ethnic cleansing, and brutal industrial labor including children; and on the other hand, the current “late-stage capitalism” involving debt traps and monopoly —

Those few decades were enough to convince liberals of the “true” benevolent nature of this system. Just don’t look outside of your own immediate circumstances, nor read history; that might ruin the illusion. Don’t even ask your parents what their own life was like during this fabled golden age.