Capitalism is a system. When you burn your food that is not end stage cooking, but a failure to manage cooking as a system. When your worn tires blow out while speeding causing you to fly off the road that is not end stage vehicular mobility, but irresponsible driving.

The last time Capitalism went unchecked and tried to eat itself was the Great Depression. That was ended by controlling Capitalism with strong regulations, high taxes on the rich, and pervasive union membership of workers. And the Social Security system and Medicare were also a part of that deal.

When people talk of "end stage Capitalism" all they are saying is that they lack the will and the power to use the tools we already know work to solve these problems.

Perhaps they're saying that the system inevitably evolves into a subset of the state space regardless of controls.