A Prof. Erik Olin Wright here talks about the conviction that it is impossible to challenge the nature of ‘capitalism’ (whatever we take that to mean) itself, through incremental institutional reforms within our current economic system. This is claimed by much of the far left, essentially for ideological reasons.
His conclusions for the whole lecture can be heard from 55.30, finishing with his thoughts on the ‘limits of possibility’.
He points out that this conviction is not based on evidence. It comes as part of a package of beliefs. But if just a few of those beliefs are a bit off, I would say the conclusions may also be off. It’s a very limiting conclusion to draw and I am not certain about the certainty with which people hold it.