I don't know how affluent the average RFer is, but I think it's safe to assume that most of us are not in the 1% or even only the 10% wealthiest of our societies. But I have noticed that quite a few defend inadequate taxation of the rich. It reminds me of Stockholm Syndrome, or of mistreated people who defend their oppressors.
We are tribal in other ways, but in the case of capitalism so many of the have-not betray their tribe and fight for the tribe of the haves.
Why is that? How have the ultrarich managed to convince the majority that they and their wealth is untouchable?
There probably are a number of possible factors.
For one, support of capitalism has been ingrained in Americans as patriotic, since the Cold War created a national identity which is capitalistic and virulently anti-communist. So, there's been an underlying fear of being called a "traitor" for not giving 110% support to capitalism.
Secondly, for most of the generations alive today, the U.S. economy and society has been mostly insulated and enjoyed a relatively high standard of living, which many people have been (mendaciously) persuaded into believing that it was due to capitalism.
Related to the second point, even low wage workers believe they get a better deal under capitalism than under socialism. However, what they don't realize that they only get a better deal under
American capitalism - something they wouldn't get if they were living under Guatemalan capitalism or Chadian capitalism. (Though I hear German capitalism isn't too bad, as you get better health benefits and more paid time off than Americans get.)
What's really been missing from the current discussion - at least a difference from what I remember from earlier decades - is a strong public voice of support for organized labor. Labor unions still support a capitalist system, and they use their right of free association and freedom of speech to advocate for better wages and working conditions for their workers. This is why support of capitalism has been rather strong among the union rank-and-file (at least traditionally). Liberal support of a strong and robust labor movement was actually quite helpful to capitalism.