This is a really good post, but I just want to add that, economically speaking, exploitation is not about a specific number.
it's an important observation that someone making $200k a year is still far and away from the actual ultrawealthy. But where's the line, who gets to draw the line, and what does the distinction represent? Especially across countries and cultures, where that line will tend to vary wildly! That's a really reasonable question, and there's a good answer.
This was Karl Marx's central work, basically. He wrote Das Kapital setting out to explain some recurring features of capitalism as the system was growing, developing, and taking over the world: that it tended to accumulate wealth at the very top, that it tended to have a major crash every ten or so years, and some other features.
What he was able to show - and that was pretty definitively accepted by other even pro-capitalist economists at the time - is that capitalism is exploitative in an economic sense, meaning that an 'owner' of a business made money off of someone else doing work.
For example, I worked for a guy named Gary who owned a pizza shop. I was paid $14 an hour, but each pizza cost $8 plus tax. I would make between 20 and 50 pizzas in an hour, depending on the time of day, so across my four-hour shift I made $56 (before tax lol), but I made the business $160-$400. Some of that money after I'm paid goes to buying more ingredients, some of it goes to pay off the building's rent, but everything else went to Gary, who did nothing except steal from our tip jar.
Gary probably made somewhere to the tune of $150-$200k a year, off of me and my high school coworkers slinging pizzas all day next to an 800-degree oven.
In contrast, a dude I knew named Nick made between $150-200k every year as an ironworker and dockworker. He was paid well, but he wasn't taking from anyone else's livelihood - in fact, he still made more money for the construction company than he took home.
Gary was, in an economic sense, exploitive. Nick wasn't. And Gary is who socialists have a problem with. This is the distinction between "working class" and "owning class", not a number. And it's an issue not just because it's frankly an antisocial, cruel way to organize society, but because it actually causes crises.
This was another thing Marx figured out. The reason that capitalism tended to crash, over and over, was because of the accumulation of wealth. With successful businesses under capitalism, Gary keeps making more and more money -- I and my coworkers keep making $14/hour or only marginally more. Eventually, that means I cannot buy a pizza at the place I work, or much of anything else for that matter. When that happens, people stop buying what they used to, profits crash, and capitalism has a crisis.
Understanding this is what class consciousness is. Your class is not the number on your paycheck, it's whether or not someone is taking part of your paycheck from you, or you're taking from someone else's labor. It's applicable in America where you're talking about median incomes in the tens of thousands of dollars versus billionaires, it's applicable in countries where people are living on just a few dollars a day; the system that oppresses us is international and revolutions have to target the real exploiters, or risk failing to transform society into something better.