Yes, but evolution is much slower than cultural change. In principle, it is possible that a society might have very high and very uniform standards for the minimum wealth per child, so that it would take a very long time before evolution undermined these standards noticeably. In the meantime, it would make sense to speak of a Malthusian equilibrium.

In reality, of course, such a situation is highly improbable and (to my knowledge) not attested historically. So it's not really a mistake to equate a Malthusian equilibrium with awful poverty and constant threat of famine. (The latter would of course also have its analogues in a Malthusian upload society, which are not hard to imagine.)