All over in the right professions. Accountant, probably basically everywhere for example. I imagine it wouldn't be hard to pull 70k doing b2b sales. Plenty other white collar work probably gets you there too. Skilled trades also very well compensated today and in demand as well.
Raleigh-Durham Metro, Metro Houston, Metro DFW (imo not the South), Charlotte Metro, and Metro Atlanta off the top of my head and based on median household incomes.
That said, assuming you could afford a 2k square ft house with a backyard in a highly desirable neighborhood similar to what Palo Alto is today on an average person's salary 50 years ago doesn't seem realistic.
Also, 50 years ago, redlining and race as well as gender based discrimination in most jobs was the norm, so unless you were a white (which itself was a narrower term than today) man, there was a glass ceiling, and most jobs that were supposedly high paying in reality largely limited hiring to a subset of Americans.
Additionally, the rural-urban divide then was more severe than it was today. People from those households like Marc Andressen literally didn't have piped water growing up back then in the 70s (he's recounted the story a lot).
Long story short, I don't buy a lot of the nostalgia for the 70s and 80s I'm seeing in this thread - it's very boomer urban white man coded.
True, but the median American is also not college educated or working in a skilled manufacturing industry, but is true at the 60th-75th percentile in most cases.