Under a fully socialized medical system you as a consumer do not have the option to shop around for a different alternative to your current health care insurer.
This is not the case with a single payer system. Although the direct decision is removed from the consumer, the government still shops around for the best price for products or services.
It's definitely not the best solution but at least in the US you can look for other companies to sign up with and while that process can be hard...
Unless you're poor or your employer gets a kick back to offer a single health insurance option or you have a pre-existing condition. ...it does mean that 1 denial of service is not the end of any chance you have of help.
You're clearly in denial about the reality of poverty and income mobility in the U.S. The fact is that 10% of the population has de facto zero access to healthcare except in extreme emergencies. All but a small portion of Americans have low-quality health care options and anything related to a traumatic or chronic condition means going bankrupt.