I think late-stage is usually used to imply that while many of these mechanics can be useful as a way to efficiently allocate capital in some earlier stages of capitalism where private companies are more distributed and act less like governments, that when they finally go to their eventual conclusion and companies meaningfully go toe to toe with the government (and even finish regulatory capture), it becomes pathological and harmful.
In the United States in the late 1800s, wealth was incredibly concentrated in a few families and as far as I can tell they ran the government. So it was late stage back then, would that make now post late stage?
On the other hand, I would think that late stage capitalism would be defined when there is regulation of greed to prevent predatory and monopolistic practices that reduce competition. Or maybe that should just be called sustainable capitalism?
I'd say, more succinctly, that late-stage capitalism is when the maximizing of profit ceases to simply be a means to an end, and becomes an end in itself.
At least, that's more or less how I personally view it.
