Yeah, I don't have a strong opinion on the original claim. I don't think it's clear that it's impossible to fund the kind of universal healthcare we'd want without raising taxes but I do think that's likely. I think it's probably "easy" (in terms of having the money available in theory, not politically) to fund universal healthcare at the level we'd want while raising taxes on each individual by less than they were paying for private care. But these are guesses.