To play devils advocate* because providing world class universal free at the point of use healthcare for a nation of 60 million people is a gargantuan undertaking, that requires masses of material resources to be utilised and directed. It requires a huge amount of money, that needs to be reliable for years upon years in advance, not to mention the massive costs involved in researching and producing the drugs and other medical technologies, years upon years of training for doctors and nurses, the infastructure and follow up care and all the rest of it. This requires a lot of planning, which of course could be done democratically, but not without some degree of centralisation. Perhaps nationalisation is more suited to that kind of undertaking than people realise, as the state is in a much better position to provide those necessities than voluntary organisations of working class people? And wouldn't any democratic planning organisation that took on this role in an anarchist society end up becoming a de facto state or authority of some kind?
And as much as I admire what took place in revolutionary Spain, can it be compared in both scale and sophistication to the modern NHS? Has any anarchist society been able to come close to this? Furthermore would an anarchist reject the NHS in favour of a non-state organised system, even if that system was unable to provide the same high level of care we so often take for granted?
There's also another point which is the NHS was seen by Bevan and much of the democratic socialists who helped create it as an extension of the principles of mutual aid and collective provision into the post-war era. For them it was the logical conclusion to a centuries worth of experimentation and DIY mutualism in providing welfare system that has its roots in funeral societies and co-ops and so on. Which is why the insurance principle was rejected outright, and why it is based on medical need and not ability to pay, and even to this day in an otherwise neo-liberal society healthcare is not seen by British people as a commodity as it is in other societies that had state-backed private insurance healthcare systems.
*so don't necessarily take all this as if it's what I feel is best or ideal, just want to see what people think of this.