The width of the spectrum of political views for 65% of people used to be relatively narrow.

That's increasingly not the case.

Capitalism "Choice is good!"

Politics "Not like that, not like that!"

I don't believe that political views used to be narrow, I believe the political views you were allowed to actually express were much more narrow and everything else was repressed.

Really depends on the region. There's lots of opinions/ideas/directions/parties in many countries with lots of overlap. In the US... I'm not sure how relationships, that actually talk about things, can survive if partners have different party preferences.