I believe the one major change has been about trust in institutions. It used to be that census, or unemployment data was, for the purposes of political discussions, assumed to be accurate.

Now, unemployment data was so-so-fake just before the election, and the-best-numbers-ever just after the elections, although they changed only marginally. This sort of bad-faith argument will lead to a complete breakdown of civil society if continued.

This may just be a symptom of polarisation, though: Republicans (and yes, it's almost exclusively Republicans, so far) can only get away with it because their voters have staked their identity on their team's success, and are willing to go to such extremes to protect it. Yes, democrats have similarly absorbed politics into their sense of identity, and it may just be luck that they ended up getting reality as their playground.