What is the "middle class" then? Do the vast majority of these people have to sell their labor in order to survive...? Or are most "middle class" people small business owners and the like?
People like to define "middle class" with income-based definitions... but this isn't very useful when analyzing the socioeconomic reality. What this term plays into is divisiveness and people's desire to distance themselves from what is looked down upon in this society - in this case, being "poor," which the working-class has become associated with. More than anything, it is a psychological thing. "We're not rich and we're not poor... we're middle class." But if your employer fires you, which is easy to do if you're an at-will employee... what are you then?
The "middle class" is just a paycheck or two away from facing the truth of their material position. It is a baseless identity to cling to, in all honesty.
That being said, some segments of the "middle class" may actually form an important strata of the working-class - namely, that strata which aligns its interests with the state and with bosses. Some of this is also based in identity, but I don't think it can be said that managers, DAs, police, etc. are working-class in any meaningful way, whether in interests or actions.
the passage of time has undoubtably wildly skewed our ideas of class and wealth
Skilled workers, professionals, government, small(very) business owners, rentiers(to a point), classically, imo. Nowadays those people would be considered in the top income brackets at least in the north east. Sell labor(ie "work for a living"?) in order to survive, yes and no. It's also all in how you define it.
I feel basing it on income is helpful but only tells part of the story, across the country income and cost of living wildly vary.
Absolutely. Another thing I'd like to point out is that the middle class is often equated with the working poor now. In ultra capitalistic and materialistic societies being middle class isn't seen as a favorable position to be in.
I suppose people find some comfort in falling into a group as opposed to not especially if they feel it enhances their position in society even marginally if at all.
I think about my immediate family who were military, government, athletes, electrical engineers, rentiers, and small business owners and I saw them as being middle class or upper middle class in the 40's-00's. At some point maybe they were no longer middle class? I know if I were to apply my ideas of class to myself, I don't know where I would place myself. A lot of being middle class isn't about income as much is it as about profession, I feel like. After that I suppose it would boil down to assets and then at the point can one still claim to be middle class?