Very unlikely to be true. Pick up Ezra Klein's Why We're Polarized, he takes a look at the degree of polarisation in US society. Even during the cold war, civil rights fights, assassinations, students being shot on campus and cities on fire and McCarthyist persecutions the political system itself continued to function without much hiccup.

Today's institutions are relatively stable, as is the world situation overall, yet polarisation is significantly more extreme than during past times in history.

Institutions in the US aren't much more partisan then they were at any other point, because institutions in the US in particular are very independent and hard to take over. This has nothing to do with the state of the real world and everything to do with the uncontrolled flow of information.