Excellent points.
As long as ACA simply focuses on paying the bill, no matter how steep the price, insurers, hospitals and medical suppliers have absolutely no reason to lower their charges.
The ACA (and the British NHS, etc.) are based on two premises:
(a) That society as a whole receives less than the optimal amount of health care services, thus causing unecessary suffering and premature death.
(b) That this should be changed by subsidizing health care. ACA is intended to increase consumption of medical services, which must be paid for.
One side denies the reality of premise (a), the other of premise (b). Both sides need a dose of reality--a commodity in short supply on the banks of the Potomac River!