I like this framing. The differences between these two groups is much bigger than the differences within these groups, at least at some fundamental level. There is as always, nuances, and a grey area somewhere at the transition.. but overall yeah. You are either in need of some sort of income related to something you actively do, or not. There are of course ways to distinguish subgroups, but that is often as much or more culturally / socially than purely economical / financial.