I like to be simple about it.
Do you own enough property or assets that they provide for you? You're not working class, you're owner class.
Self employed? Working class.
Own a business and it pays all your expenses? Owner class.
Are there gray areas and nuance? Sure. Life is replete with nuance. Exceptions to every generalization and all that.
For me, the distinction lies in whether your work is necessary for your survival. Another distinction is who you're beholden to.
In this sense, the picker/packer at Amazon and the developer that makes 250k are in the same boat.
Nuance is found in management and supervisory roles. Their function and alignment are with the ownership class, but still rely on pay to survive. They are in a sense half in and half out, but despite what they believe, they are still workers.
The line is blurred further at the c-suite level and to the extent that there is a golden parachute of some sort, the line disappears.
Nuance. You can't expect hard and fast rules to function in a world that is made of continuums.
I see gender similarly, it makes for a used comparison here. Do I have some ideal and concrete concept of masculinity and feminity? Sure, most people do. I also (like I believe a majority of people do) understand gender is a continuum, not a binary.
So, do we work to the benefit of the management? Yes, they just don't see it that way. To the benefit of the c-suite? Also yes in that their worldview is truly unsustainable. They would hate us for it because all they can see is quarterly gains.
Wasn't the first time this year, won't be there last.