I have a question for all you unrepentant capitalists out there -- why is it that massive concentrations of wealth pretty consistently tend to lead to a decreas

I have a question for all you unrepentant capitalists out there -- why is it that massive concentrations of wealth pretty consistently tend to lead to a decrease in the overall quality of life? Because if the boosters of capitalism are to be believed, the path to making society better on balance is to enable people to accumulate unlimited amounts of personal wealth and then sort of let that wealth diffuse through the people around them. This isn't actually happening in places where wealth from the tech industry is concentrated. The rising tide is mostly just sinking everybody, and obliterating everything that isn't explicitly about making money in its path. So what gives? How can you argue anybody is better off for all this?