The hullabaloo over "If you like your doctor, you can keep your doctor" goes a long way to explaining how health-care used to work in the US. Most simply it was a free market and free markets work.

In more detail: Independent doctors (and their staff) functioned as buyers' agents would refer patients to specialists. "Doctor-Patient Relationship" and "Referrals" were the two main components of the system. Knowing that DR. JONES referred PATIENT SMITH to them, the specialist would treat PATIENT SMITH well and charge a reasonable amount.

It was unfortunate in that you had to "get in" to the system by finding a good doctor. It was (and more now than ever is) hard to "find a good doctor." Most are no longer accepting new patients, but it served all those parties. Doctors would have repeat customers. It'd reduce their work of learning new patients. Etc.

Without such a family doctor, you would go to a provider without a referral. The provider would then know it could gouge you without risking a referral relationship.

However this system was sub-optimal for insurance company profits and large scale providers. Which is exactly who pushed Obamacare, and lead to the break-up of so many of these relationships.

As background, Health Insurance has lists of "approved providers" which they carefully curate. The most straightforward method of breaking up relationships is to exclude providers. They also put these "good doctors" (from the patients' perspective) into plans with expensive premiums. They also churn. By raising prices selectively between plans with different providers insurance companies can encourage patients to "try out" a new doctor this year. They also churn provider lists.

This means Insurance companies are now a more powerful source of referrals. They also prefer institutional providers. Between both of that, fewer providers care about where their patients are coming from. The patients often don't have much choice where they go (one of 9 different locations of the same conglomerate) and don't know enough to make an informed decision anyway (as their family doctor used to do for them).

All of this is brought about by the individual mandate. It's not a free market if you're not free to abstain. By being forced in, cash buyers became a smaller segment of the market. Cash buyers were the very people holding it all together by selecting doctors of their choosing and forming these relationships. With these doctors going out of business (largely retirement) and being replaced by institutional providers it's just getting worse.