Well, and pre-cubicles, it was just a bunch of tables in a big room surrounded by managers in offices.

The open workroom was a relatively short fad pioneered by Frank Lloyd Wright. If you look at office buildings before that, they're much more similar to houses and apartments. Lots of rooms connected by hallways, staircases, and atriums. You can imagine the difficulty and expense of lighting a large open space without electricity.

In Europe I see a lot of companies with open space workrooms with some cubicles, maybe 30-40% of workers at those companies seem to work in them.

No, it wasn't. Most companies had separate offices, individual or with 2-4 desks in them.

There are still many companies with cubicles, although they do seem to be getting rarer.

Cubicle, you say? LUXURY! We had to code 12 of us to a desk inside a cardboard box in the middle of the road. At the end of every day, Pointed-Haired Boss would replace us with A.I. and fire us, only to re-hire us the next day at half the salary.

(With apologies to:)

https://en.wikipedia.org/wiki/Four_Yorkshiremen