Those rankings are of course heavily influenced by the methodology and metrics chosen. Differences can be very small but obviously even a very small relative difference results in a higher or lower ranking. That's how rankings work.
For instance, in this case: "The U.K.’s health system is the top one for affordability... In the U.K., the National Health Service (NHS) provides free public health care, including hospital, physician, and mental health care"
This does not mean it is 'better' or that others are in fact unaffordable.
For instance, in France a visit to the GP costs 30 Euros but 28 are covered by social security and private cover. Arguably 2 euros make no difference vs. "free" but it's just that you can beat "free" when ranking on affordability.
That being said, I think anyone with experience with the UK and other European countries' healthcare systems will be surprised, shall we say, with this ranking overall...
For instance, in this case: "The U.K.’s health system is the top one for affordability... In the U.K., the National Health Service (NHS) provides free public health care, including hospital, physician, and mental health care"
This does not mean it is 'better' or that others are in fact unaffordable.
For instance, in France a visit to the GP costs 30 Euros but 28 are covered by social security and private cover. Arguably 2 euros make no difference vs. "free" but it's just that you can beat "free" when ranking on affordability.
That being said, I think anyone with experience with the UK and other European countries' healthcare systems will be surprised, shall we say, with this ranking overall...