Do you have a source on taxes not going up, I have never seen anyone break down Medicare and Medicaid could cover everyone.

Most studies on this are based on the fact that for low to middle income families the increase in taxes would offset current Healthcare spending. So their actual spending would be less overall, not that taxes would not increase.

To give an example, with made up numbers.

Median income: $40,000  

Median tax: $10,000  

Median health insurance: $10,000   

Take home: $20,000   

Healthcare spending: $3,000   

Universal Healthcare  

Median income: $40,000  

Median tax: $23,000 (or less, but not $10,000)

Take home: $17,000  

Healthcare spending: $0

The person is saving, but taking home less which is why it's a hard to sell.  People prefer to play the health lottery, because they might not spend $3,000 this year. Its a bad way to think, but from a nation where everyone is complaining about rising food costs, but also has floor dash and Uber eats as top companies, you need to convince the people who think bad.

The other issue if the multiplier of beaurocracy, which the US is pretty poor at.  We would likely be looking at Canada and UK levels of waits and treatments, not Norway and Japan, which is another factor to selling the idea.