Incommensurate philosophies

I've become a nihilist in regards to political economy. On the one hand, we have the conservative/libertarian/Austrian "cut taxes" ideology (regardless of massive deficits). On the other hand, we have the modern liberal/Keynesian "spend public money" ideology (to jumpstart production again - do we really need to prop up unprofitable industries?). But there is this logjam where no real progress is made (no side is more convincing than the other) because there are NO AGREED UPON FACTS. If we can't agree on what is going on on the ground, there is no real debate in the discourse - it's just ideologies clashing and trying to gain power/influence. Neither party has the proper approach. How can these incommensurate ideologies co-exist? The crisis needs to get worse to tip the scales.

The real question for me is: would capitalism ACTUALLY COLLAPSE IF WE DID NOTHING? Would there be a real threat of revolution? Are modern liberals vindicating Marx? Or is it just Polanyi's double movement?

Do those on the left really want capitalism to survive, given the environmental destruction and social polarization? If we were serious about change, it seems like we could have done much more (i.e. climate change, relocalization). What would the Republicans have done if they were in power? Would they really have had the balls to "do nothing"? (i.e. in the face of the real risk of socialist revolution or otherwise)...