No. We have a stereotype of arrogant rich people, but that's more the high spenders who are driven to show off wealth as fast as they earn it.
Reading "The Millionaire Next Door", hearing Dave Ramsey and others, most of those with a million dollar plus net worth are small business people who worked up from blue collar jobs or saved and invested over 30 years. They tend to be modest and have high integrity.
For the middle class, it runs the gamut from low self-esteem to high.
For the lower class, low self esteem may come from lower achievements in life, but many criminals have HIGH self-esteem. They think they are better than everyone else and deserve it, so they are justified in taking from others or hurting others.
It is actually counter-productive to endlessly nurture self-esteem without correlating it with achievement. That is the failure of social justice warriors. Told you are so special, should always feel good, that it is a sin or crime for anyone to tell you that you're wrong or set boundaries you don't approve of. They freak out at the idea that someone is in another room expressing views they disagree with to an audience.
Their logic is: "I don't like it, so it is bad. I'm good and love, so they are bad and hate. Their hate speech is hurting me, and my feelings define reality. How dare he attack me! Everybody, let's go shout down the evil hater! If that doesn't work, they hurt all of us, let's go hurt them." That's the emotional reasoning of social justice warriors beating up people from Middlebury to Berkley to Evergreen State. Very high levels of anxiety and actual mentally ill thought patterns (projection, paranoia, catastrophism). And they are mostly the adult children of the middle and upper class.
To literally throw a tantrum because someone wants to state an opinion you don't agree with and demand their jobs or lynching is not a sign of self-esteem or self-control.
This last section draws from "The Coddling of the American Mind".
The Coddling of the American Mind