capitalism is the least bad system...

Trouble is this is at least four very different types of statement
The is an improvable this is the least worse - well maybe....
Or their is the challenge on the level of idealism. I mean the challenge to try to think about a different system. our failure to think beyond the system we all know is flawed is after all a challenge to the imagination (and its failure is our failure to think beyond a box). The statement is then a gambit - you will to be able to imagine a better system: A probable fallacy.
Thirdly there is a statement about practical limitation. The statement runs that even if one can define a better system in the short term the pain getting their is too higher price to pay- or worse will lead you astray, so you never reach your promised land.
Finally there is a hard edged assertion that has prisoner's dilemma written all over it. We need to trust other folk but also nations, to get out of the cell, but if we trusted one another we would now have the current system (which is built on lack of trust, but of course encourages it).
The result is then that the world finds it just too difficult to move beyond the system that happened to be (in part) in charge when one or two powers industrialized (leaving aside whether capitalism and industrialization need it each -- one suspects there is nothing as simple as a yes no here,), as this system then evolved as it expanded to cope with the collapse of the old imperial order (again for very many reasons, including capitalist propaganda, but there is nothing necessary in the timing here).
In short we have understood the triumph of the machine through the capitalist lense from so many angle at the same time, and for so long, that we appear to have lost all hope or dreams of moving beyond its many jagged facets- all we can hope for are adhoc mutations....