for myself, i don't think it is the end of western democracy. i think the us system doesn't achieve what it seeks. the princeton study is evidence which in my view supports that argument.
but i also think the us can get back on track to being a responsive democracy. it just needs to challenge some of its self evident truths. or even just to interpret them more flexibly.
eg the idea that a corporation is a person could use some further thought. it can be in some ways. but not in electoral terms.