Cubicles got so much hate because they were worse than private offices that came before them. Now open floor plans are getting hate because they’re worse than cubicles so rose-colored glasses makes cubicles the nostalgic dream.
I don't think there was ever a time where every office worker had their own office. Only the big boss got their own office and everyone else had desks in a large room. The open floor plan we have now is pretty typical of what they used to look like.
There are plenty of places where offices were the norm some years ago. When I worked in Germany the standard was either single Offices or team offices With max 5 people. In the US IBM also had offices when I contracted there. Microsoft always talked about their offices as important. Developers sitting elbow to elbow in a room with dozens of people is a fairly recent development from what I have seen. The need for headsets to get some quiet also seems fairly new.
That's interesting, but I'm unsure how much we can generalize from some photos. For example, I wonder how much "photogenic bias" [0] and survivorship bias exist in such photographic evidence. How many photographers of the time would take a picture of a hallway of private offices? And what editor would keep such photographs for posterity?