It's prob important to know level of coverage and % of income it costs vs absolute numbers which is fairly meaningless.

In Australia, the government spends over $70B on healthcare, but collects only around $10B through Medicare levy surcharge. The only reason your healthcare spending in Australia seemed so low is because an overwhelming majority of the cost of healthcare in Australia is covered through general taxes, and not through the Medicare tax. Even if you focus on Medicare benefits only, the Medicare levy surcharge only covers less than half of the Medicare benefits.

That said, healthcare in Australia in fact is cheaper than in the US, but not as much cheaper as you think it is.

I live in Australia and that doesn't seem out of the ballpark. I pay the equivalent of USD$1.3k a year in levies and USD$100 a month for health insurance. Australia doesn't have access to the same level of care either (for example, bleeding edge cancer treatments or experimental medicine).

I also pay substantially more in other general taxes (compared to the US), which ends up funding healthcare as well.