The precedent of pretty much every other first world country would disagree. You seem to be fundamentally making the assumption that the economic benefits of SP UHC would be dwarfed by the reduction of margins in the health and pharma sector, and elimination of insurer middlemen.
I'm not making an assumption, I'm making an observation. We pool our resources through premiums and taxes to reimburse providers for services rendered. That spending--our collective spending--has to cover the costs of those providers, plus provide some degree of margin so they can continue to invest in capacity and innovation.
The idea here is to hand over all responsibility for those reimbursements to a single entity with monopsony power, which then rapidly reduces the total amount of reimbursements its willing to pay out. This, in turn, forces radical disruption among providers who must immediately cut costs drastically or go out of business. So what are those costs?
Two-thirds of spending on personal health care in this country flows directly to hospitals and physician services.
According to the federal government, based on mandatory cost reporting by Medicare-participating hospitals, the input costs of a hospital (which our collective spending, financed by our premiums, covers) and their relative contributions look something like this:
What are the costs that make hospitals expensive? Turns out it's people. The time, expertise, and effort of the workforce tends to be a major component of costs. 60-70% of those costs are the expense of giving people paychecks. Everything from clinicians to finance folks to IT staff to janitors. That's why cost control is so difficult; hence the concept of "bending the cost curve" instead of reducing our year-over-year spend.
CMS doesn't collect similar data on physician practices, but
MGMA's survey of cost data from thousands of practices tells the same story:
There are two possibilities:
1) Single-payer really would, as you now seem to suggest, simply root around the edges, trimming some margins (primarily of the most easily vilified actors) and displacing some stray admin staff. In which case it won't save nearly as much as billed, and thus requires more revenue to flow to the government to cover its costs. Or,
2) Single-payer
will take a serious whack at costs, which means significantly more disruption, displacement, and pain for the workforce than its adherents have thus far been willing to acknowledge.
I suspect in reality (1) would prevail for practical and political reasons, which makes the financing that much more challenging and the rationale for this approach weaker.