The delicacy and the art of cunning craftiness engendered false dependence and left all men bereft of anything of value, and, in mediocrity, that which was significant was stolen by the thief. But poverty protected the outcast's slender hope...
Naked from the violent seas of a great storm, survivor clings to cliff only a couple of feet left to get to the top. Even then, at the top he must get warm quickly.
This is not realistic art, it's "Reality Art". It's still symbolic, but it depicts in a certain way the more realistic "it's worse" ("pire encore") scenario.
The song is about the poverty of the poor being their best protection, "they" cannot steal it. Nothing of value, except everything. The poor are rich -- well, check it out. They still have their minds. There are just a lot of other things wrong. If they ironed them out, they'd be all right.