No. It will eliminate the rationing going on today. The U.S. already rations care based on ability to pay: if you can afford care, you get it; if you can’t, you don’t.
In 2017, an estimated 30,000 unnecessary, preventable deaths were linked to lack of health insurance. Many more people skipped treatments that their insurance company refused to cover. Those are forms of rationing.
A single-payer system will ensure that everyone has access to a single tier of high-quality care, based on medical need, not ability to pay.
Long wait times for non-urgent procedures in some countries, e.g. hip replacements in Canada, are often cited by opponents of single-payer reform as an inevitable consequence of universal, publicly financed health systems. They are not. Wait times are a function of a health system’s capacity and its ability to monitor and manage patient flow. In recent years Canada has shortened wait times for non-urgent procedures by using better queuing techniques. In the case of urgent care, wait times have never been an issue. Moreover, we spend twice as much per person as Canada does, enough to assure that we wouldn’t have waits in our single payer system.