This is an issue we have discussed many times here, from various perspectives.
The issue of postcapitalism is based on a decision by free agents to replace capitalism with another, better system, based on their decision. Based on a new set of values, best some form of communism…
The attempt to say that capitalism is going to transcend itself through its own internal dynamics is likely to be another way to justify capitalism by doing nothing.
One of the weaknesses of marxism is its tendency to posit economic dynamics beyond the free action of the revolutionary. But that has backfired. We don’t have to wait until capitalism is ‘finished’ somehpw. We judge it to be a failure on its own terms.
This should be obvious but economic ideology has such a grip on us we cannot stand up to the whole game.