Capitalist class wrote the US Constitution. The middle working class were excluded in the process, people who did not own any land or were in debt, women, African Americans, and Native Americans.
To me I think its 50/50 somethings have changed and some haven’t. Wealthy people still have power, still getting things done their way but I think that the working class have a chances to advance with hard work to become part of the wealthy class.
They feared that the working class would rise up against them as they knew. The majority of the population is made up of working class people and they wanted them to stay that way. They also wanted to keep their power to totally control the lower and working classes.