Herd immunity and globalized viral tests help prevent the propagation of pandemics
Viral propagation in a population is an exponential process. Relatively small changes in the number of people involved in the chain of propagation can have a very large effect on the speed at which it spreads. In a private healthcare system, access to vaccination and viral load tests is restricted to people who can afford them, leaving a significant part of the population as a vector of uncontrolled spread. On the contrary, in a health system where everyone potentially has free access to these resources, there is no such risk population group. Limited resources can be prioritized to people at risk of infection regardless of their income level, following medical rather than financial criteria. This increases the number of protected persons among those at risk of exposure to the disease and provides the authorities with greater control of infected persons for quarantine purposes. America is drastically behind other developed countries, who offer free, universal healthcare. There are not enough resources; hospital beds, medical equipment, etc. There is no equal access to healthcare as many Americans choose not to seek care, even for the direst of medical conditions. The government prioritizes the economy over the population's health, forcing many of these at-risk people out into the public where the virus can spread. Free, universal healthcare would mitigate this risk. With equal access to healthcare and adequate resources to handle pandemics, the number of at-risk carriers would dramatically decrease, ensuring our preparedness for pandemic outbreaks.
The cost of free healthcare on taxpayers would render the money saved on healthcare as negligible at best. People would still be paying out-of-pocket taxes for healthcare that they may not even be using themselves. This leaves less money in the pockets of middle and low-income people, and would then restrict access to other life essentials because the cost of living would not change. Food, water, shelter; these could all be harder to obtain or keep with less money to spend on them. Free healthcare would not stop or slow the spread of a pandemic. The restricted access to life essentials due to a rise in taxes for the middle and low-income population would just as likely propagate the spread of the pandemic. People would fall ill due to improper nutrition, or in extreme cases become homeless because they can't pay their bills, and having unhealthy people out in the streets would increase the risk of spreading the virus. Other countries may have free healthcare, but it has no effect on whether or not they can control Covid. Some countries with free healthcare might be handling the pandemic just fine, but others--like Italy--are being hit hard by it, despite universal access to free healthcare. Changing America's healthcare system in the midst of the Covid crisis would not help defeat it.
[P1] Private healthcare restricts access to care and leaves the poor unprotected. [P2] This significantly-sized poor population becomes a propagator of the pandemic, spreading it further and faster than if healthcare was free. [P3] Healthcare should be free for everyone to help contain the pandemic and prevent its spread.
Rejecting the premises
[Rejecting P1] Free healthcare would raise taxes, which would leave less money in the pockets of middle and low-income people. With less money, there is less access to life essentials such as food, money for rent, etc. This leaves people just as vulnerable to the pandemic. [Rejecting P2] People would spread the pandemic anyway; the current healthcare system has no effect on this. [Rejecting P3] Free healthcare would not solve the pandemic problem; there is no evidence that it is keeping Covid at bay in other countries.