HMO laws allowed for-profit healthcare insurance. Groups of doctors banded together and carved out exclusive contracts to sets of hospitals and providers.
Before this I recall seeing $7 taken out of my paycheck and there were no deductibles or copays. Meds were $5.
The govt also acts as a monopsony and forces lower prices. Same effect [0] different mechanism.
[0] actually a better effect - the govt actually does force lower prices, whereas competition is subject to all sorts of other effects where it doesn't actually function to lower prices.