I have the advantage of seeing towns like Schaumburg and Rolling Meadows rise from the cornfields as I grew up in the 1960's and 70's. The construction of the Northwest Tollway (now the Jane Addams I-90) in the late 50's and early 60's opened the door to development. The boom really took off after Woodfield Mall was built in 1971. My cousins followed that path to go from established Des Plaines to remote Lake in the Hills in McHenry county, and we drove through a lot of open space to visit them. By 1990 it was largely built out.
The area may look new compared to the early 20th century homes nearer the lake, but compared to today's large lot exurbs or teardown neighborhoods the area is actually quite old (or maybe I'm younger than I think ).
Yes, you are young. I remember in 1971 going up to Park Ridge, with a group from college, to see the movie Sunday Bloody Sunday. It was an experience that I will never forget, because one of the guys had a black girl friend, and the stares we got were just killingly hostile. And then when the two men kissed in the movie, there was a gasp in the theatre, and half the audience walked out. We all concluded that Chicago suburbs were
horrible places, filled with
horrible people, and to be avoided at all costs, unless it was Evanston. BRTD back then was absolutely right!