USA really too different from English-speaking world to have similar policies?

This is from another thread, but fits here.

If, as some here claim, the benefits of UHC might not translate to the USA, isn’t it just as reasonable to argue that the advantages in top-end care are not due to the lack of socialized medicine?

If we’re being sloppy to claim that UHC works in other countries & would therefore work here, then isn’t it even more sloppy to claim that private medicine causes better transplant care?