First, this question as posed (and as finely discussed by both Doug & Maria) is what Albritton would call a question of the 'third' level of theory, the present, which he calls _history_ . It deals neither with Critique (Marx's attempt to capture the "ideal average" of all possible
"capitalisms") nor with mid-level theory (e.g., the entire neoliberal period, abstracting from continuing spatial or temporal differences). History (in this sense) is largely an empirical matter.
Secondly, for political reasons, I think it would be useful to emphasize that the growing richer or growing poorer are _relative_ to a given society. What is being described is the process 9f immiseration, but clearly immiseration is not an absolute; its meaning is historically and socially defined. (This is necessary to had off such ultra-left nonsense as a recent moralistic contrast of people in the eastern u.s. who had lost their power with the inhabitants of Gaza. Immiseration can exist at many different 'levels' of consumption.
Carrol