Design Trends: in the 60s when angular Brutalism was popular, cars were ‘streamlined’ or elegant as if it were pre-war design – but move up to the 1980s and despite the rise of post-modernism, ordinary cars became surprisingly boxy!

Any opinions or knowledge on this? I thought it was a pretty interesting that architecture and car design movements didn't really line up like one might expect it to.
I am viewing this from a UK perspective though, so we may have been behind the times car wise.

Credits: Birmingham Ringway and TV-am studios (not the best photos I could have got to illustrate what I mean but it was harder to find some than I thought)