This is easily provable with Public Choice Theory, and consistently proven in practice.
Contrary to the absurdly naive belief that monopolizing an industry will produce “efficiencies”, it has the opposite effect. All the wrong things are incentivized and no one has any clear signal of what creates value. (See “Socialist Calculation Problem“)
Antony Davies shared this depressing graph with me last week. If you’ve been to a health care provider in the last few years, you’ve felt the pain this causes in the realm of customer experience.