Well, as poorly as the 50s through 70s are viewed in terms of architecture, we now see some great international style buildings. While some of the skyscrapers and schools are quite ugly, that style did bridge well older building types and new technology and has allowed for postmodernism to take off. Keep in mind that a lot of cities' skylines are defined by buildings from that era. Chicago, for instance, is far more interesting with the Hancock and the Sears, but its 1960s boxy apartment buildings are at the same time one of the negative spots of the city.