I say its much easier to find faults in a system than coming up with a well-designed system.
However, not everyone is convinced of such faults. There is still a considerable part of the current political movements that still believe that: a) neoliberal democracy is perfect, and any failure is only the fault of who has failed; or b) communism is the perfect solution, and the failures of USSR, Cuba, N. Korea, etc were only caused due to capitalist interference.
For these convictions, a well developed critique has its merit, for it at least can question such certainties and unblock the way towards thinking of a better solution.
They are structures or perhaps models. They all fail because of people not doing what they're supposed to be doing. The only true solution would be a process that forces people to do what they're supposed to do.
And I don't see that happening... ever? Until the AI rules us at least.