Just because you have money, doesn't mean you're allowed in the club of the "elites". Besides money, you also need academic credentials, not because education is prized, but because college was where most of the upper class met friends and socialized--because for a very long time in America, it was divided into regions and each big fish in that region would send their kids to that region's Ivy league (or prestigious state) college to meet other kids from similar households that could eventually help them later in life. All the scientists and doctors also go to these colleges and then on to med school or post secondary school. I know a lot of scientists (especially in my public health days) that don't make a lot of money, but are still considered elite or white collar and definitely in "the club". They have the credentials, and furthermore, they believe completely in the idea of globalization and social progress as a barometer for all progress--economic progress, etc.
Those upper middle class people that you tout about are either left out of the elite because they don't have the right academic credentials or don't share the same ideas around social progress. Our health system is the best in the world for them because it allows for free market competition, not because we have better health outcomes, but instead that the idea that an individual can choose their own doctor. They believe in a different mythos--first, that a system based on free market competition will always be best and second, that our current medical climate is actually based on free market competition (which it's not). The reason they don't trust an individual doctor is because that doctor is actually in the elite, complete with alphabet soup behind his or her name. These doctors are all pushing "agendas" and are being put up by our government. Their argument, that these doctors are put up to keep the rich, rich and take away the livelihoods of the middle class, does seem to hold water when you look at how badly small businesses are suffering under Covid protocols. The upper middle class has enough money to get attention, but they aren't the only people who are sick of giant corporations usurping livelihoods and giving back absolutely nothing but misery.
Propaganda and manipulation work well in disenfranchised people. You are hearing grumbling from older people because they remember a time when companies paid living wages, healthcare was affordable, home ownership was possible, and college was affordable. I can see where they would want to harken back to these days. The elite point to the racism in this time and then points to the amount of social progress we have made in the last 40 years, and chides these people for thinking that ANY part of the old America was good. They like to say, "See how much progress we have made?" while cutting our health insurance and 401K plans. I'm not for going backwards socially, but I am for going back to where we were economically, but if I want that, then somehow I'm all wrong--because the truth is that if we paid people fairly, there would be a lot less billionaires. Listen to what this propaganda is promising to these people. It isn't money or fame or healthcare or education. They are promising hope. When you are working 2 to 3 jobs just to make barely enough to cover your bills--forget any emergencies, hope is the only thing you have to hold on to. So anyone selling hope is going to resonate. You have to ask not why these people are looking for a different way, but instead, what conditions had to arise in America for this many people to need hope. Their lives and situations are largely hopeless and though this is the land of the free, they often have no choices, or no good choices.