Could health care costs be kept down if people formed mutual health insurance companies?

A lot of insurance companies used to be mutual companies before their executives pushed to dumutualize. Blue Cross companies used to be "non-profit" before that was changed. I found someone's old hospital bills from the 1970's and was astounded at how low those bills were. Could the changes in health insurance companies have played a major role in the run up of health care costs?
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Yes, the changes in health insurance companies have played a major role in the run up of health care costs. Hospitals used to have clinics for those who didn't have insurance and people paid on a sliding scale according to income. As group insurance became available with some employers the clinics were forced out because the insurance would not cover clinic fees. That is a fact. Some people used the clinics even when they had insurance. It was cheaper and the quality was there!
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