There have been a couple of comments on this thread that strike me as quite self righteous. No one deserves to lose a leg especially if they have followed medical advice that is decades out of date.
I agree no one deserves amputation with the provisio that if a person has been given some information repeatedly by someone with personal experience of that information, albeit a non professional, and choose to not investigate it in the slightest for themselves then it can be hard to have the same degree of sympathy as one would for someone never given that information at all and more than a little frustration.
After all all of us found our way here and evaluated the low carb message for ourselves by being a little (or a lot) self reliant.
I guess older generations particularly have the dr knows best mentality and obedience to authority (the NHS) attitude that resist this autonomy, possibly coupled with a lack of technological ability or experience to com the research. And this may be passed down within families to younger people.