My comment should have said that absent insurers over that time period, prices would be higher than they are currently. The effect they have is on controlling the level of price increases, not on lowering price absolutely (which I doubt is possible if people wish to keep extending their lives).
I am not saying that insurers are the most effective option or advocating for them; I am only saying that without them, prices would be significantly higher.
If you need evidence, simply compare the total price of any health care service (i.e. total cash outlay by all parties) between a person who carries health insurance and a person who does not. Universally, the price of the service is higher for the uninsured as they lack negotiating power.
We have had such comparisons for MRIs posted on this thread already, given as examples of prices being much less at facilities that do not deal with insurers at all.
While I would agree that having buying power should bring down prices, this can be completely outweighed by the middleman trying to maximise profits. If prices are kept high, for instance, then you can make more money per person, so therefore having less administrative overhead per dollar made and so more profit margin.
For a non-medical example of this, just have a look at Apple, who make tons more money than their competitors, despite shifting less product, by simply ignoring the bottom end of the market.
I am not saying that insurers are the most effective option or advocating for them; I am only saying that without them, prices would be significantly higher.
If you need evidence, simply compare the total price of any health care service (i.e. total cash outlay by all parties) between a person who carries health insurance and a person who does not. Universally, the price of the service is higher for the uninsured as they lack negotiating power.