I pretend that capitalism hasn't much to do with it, but energy availability is key. Basically (contrary to the nonsense professed by neoclassical economics of all stripes, from Solow to Krugman and Hayek to Nordhaus) the economy is a machinery to transform energy into goods and services. Capitalism is somewhat better at it than other systems in a period of sustained growth, because the wasted energy of people competing for almost the same market doing almost the same thing (basically duplicating work in vain) is compensated by the overall growth in energy consumption.

However in the coming age of restricted energy availability, capitalism will become obsolete and disappear. It's already happening, we're contemplating a new form of techno-feudalism growing upon us.

I'll add this aside : some of these people with "Nobel prizes" in economics go as far as saying things like "+4°C will only marginally affect the economy as only outdoors activities like agriculture, which represents a couple percent of GDP, will be impacted". Because as you know, agriculture as part of GDP perfectly represents its actual importance in our lives: economists don't eat I suppose :) A joke I like is "the brain is only 2% of the weight of an economist, therefore its ablation will only have a marginal impact on this economist's ability to function".

Its astounding that this talking point is so sticky. I would recommend reading US history again, including the redacted sections. You don't even have to go back to the inception of capitalism in the colonial era to demonstrate that this idea is false.