Having been immersed in the left/right facade their entire lives, many have begun to see the world and those around them through that prism.
Either someone is on the same "side" as they are, or they are the enemy. There is no room for nuance, no subtle distinctions to be made, no room for alliance or cooperation on matters of great import.
Perhaps most devastatingly, there is now little room for any analysis of the powers behind the political throne, the oligarchical financial interests that could care less whether this or that President has a "D" or an "R" next to their name, whether a Prime Minister is "Labour" or "Conservative," whether an MEP identifies with the "left" or the "right."
Deprived of this understanding of the real nature of political power, the public is truly powerless to identify the real problem at the root of today's political crisis, let alone even begin to address it.