Malthusianism would be correct if our engineering and policy capabilities do not adapt fast enough to allow more people to have more stuff without hurting our ability to do those things more so in the future. Its not just about absolute deprivation but relative deprivation as well. I'd imagine if that wasn't the case, the president would be a Republican and have a 70% approval rating right now.
His prediction was never going to be correct. He lived too early during the ascent of capitalism to see that it was much more likely that humanity would develop birth control, women's lib, and one-child policies. Malthus also lived before the industrial revolution so he never learned that birth rates would naturally decline as machines replaced the need for family laborers.
Malthus has little or nothing to contribute to modern economics or culture.
