Answer: On the contrary; medical treatment becomes a privilege granted by the Payer.
Bernie Sanders promises patients that if we had Single Payer, all they’d have to do is show their insurance card, and they’d get all the treatment they need—no copays, no hassles, no bills. Doctors are promised relief from the complexities of dealing with dozens of different insurers.
All the other “civilized” countries in the “industrialized world” manage to accomplish the feat of guaranteeing high-quality care to all at low cost—or so it is claimed.
In fact, almost all of these countries have a coexisting private sector, and thus are not correctly described as being “single payer.” The one that most closely fits that description is Canada, which has virtually outlawed private payment for “covered” services.
British Columbia is defending against a lawsuit brought by orthopaedic surgeon Dr. Brian Day of Cambie Surgery Centre, in which he argues that “patients should have the constitutional right to pay for care in private clinics if waits in the public system are too long.” Government representatives argue that “wait lists are not the fault of the hospitals or themselves but the fault of the doctors,” Day said.
“There are two wait lists,” he adds. “There are the patients waiting for surgery. Then there are the surgeons waiting to be able to do the surgery…. The surgeons are waiting because they can’t get operating time.” There were almost 72,000 adults waiting for surgery in B.C. at the end of April 2015.
Sanders’s own state of Vermont, in its program that has so far failed, is evidently following the Canadian model. The legislature voted down a provision that would have protected the right of patients to privately contract with the physician of their choice.
The Hillary Clinton model of “health care reform” would have criminalized care outside the government-approved system. Possible constitutional restrictions on government’s ability to restrict a patient’s ability to obtain treatment for which he was willing to pay were discussed in the documents of the Clinton Task Force on Health Care Reform. The public-private partnership was envisioned as a means of “outsourcing” violations of fundamental rights to liberty and property.
Medicare is administered by private contractors (carriers), and care in both Medicare and Medicaid is increasingly delivered by managed-care cartels—which are not subject to the Constitution.
Care should not depend on ability to pay, insist single-payer advocates, who deplore a “two-tier system.” There is no doubt about which tier is preferred. 
The safety net for Medicaid patients unable to get treatment is private charity. But even this can be denied by the single payer, partly on the basis of “distributive justice,”  as in the case of Charlie Gard in England, who was virtually a prisoner in the hospital. The ability to use money to obtain care is precisely what single-payer advocates propose to eliminate.
For those who think that government offers administrative efficiency and simplicity, exhibit A is this 2013 photograph of the regulations implementing the Affordable Care Act (ACA or ObamaCare) There are more now. Recent Medicare regulations for the MACRA/MIPS/APM are a crushing burden on private medicine. These add to the constantly growing volume—130,000 pages in 2001. 
- If you have to obtain government permission to buy something with your own money it is a privilege, not a right.
- The supposed “right to health care” abolishes rights to life, liberty, and property.
- Summers WK. The effect of OPM (other people’s money) on medicine. J Am Phys Surg 2009;14:118-119. Available at: http://www.jpands.org/vol14no4/summers.pdf.
- Truog RD. The United Kingdom sets limits on experimental treatments: the case of Charlie Gard. JAMA 2017;318(11):1001-1002. doi:10.1001/jama.2017.10410.
- Charatan F. US doctors call for simpler Medicare rules. BMJ 2001322(7287):638.