Hmm, yeah I take it that the description is not perfect there.
That said, I’m not sure how to fix it. The point really is that it isn’t a better vs worse score or something. Hypothetically the staff engineer could be blowing that $600k on… I dunno, I can’t imagine how to waste $600k a year, boats I guess, and not end up with the assets.
It is definitely an extreme case, though.
"If you own a company that employs people, you are upper class."
Tons of people own companies where they employ people, but still put in 50 hour work weeks and bring home less than $100,000 a year (or worse) without growing the company's value. In this discussion's context, I would put the staff engineer making $600,000 way ahead.
Owning cash is still asset ownership. Owning a failing business is not necessary better than owning hundreds of thousands of dollars. Plus, owning stock is still business ownership.
The quantity of ownership is important, otherwise any American with an invested 401k is part of the owning class.
I prefer the distinction of: "If you need to work to live, you are the working class". Though even that falls apart when talking strictly about income, as different people use their money differently. One person may turn $200,000 salary into early retirement while another lives paycheck to paycheck until death.