IMO, the fatal flaw in our system is that all our electoral dynamics were always zero-sum. There can only ever be one winner in most of our elections. Per Duverger’s Law, that sets up an inherently divisive mechanism, and we are merely seeing the end result of a long march towards the inevitable endgame.
When this is all over, at bare minimum we need RCV. Probably some level of proportionalism and parliamentarism as well. If not, we can expect this crisis to keep happening - just like the Romans…