It's actually quite simple
The only reason it got complex for you was that you were trying to score a political point and needed to shoehorn the phrase to fit.
The definition of a "working person" is quite simple: Somebody who is employed by another, and whose employment is "at will"--not protected by a personal contract or other form of "golden parachute". In other words, fundamentally, a "working person" is somebody who is dependent on an employer for the necessities of life, and who materially suffers when employment is lost.
See also "wage slave".
--Robert