Thing is, at one point, he writes the following about the history of medicine:
And I'm not sure what to make of that. It doesn't feel quite right to me. He himself acknowledges that there was already a lot of surgery before 1935. Aside from that, the 19th century had seen the germ theory of disease, which provided the theoretical foundation for many advances in hygiene and the prevention of illness - though, of course, a lot of the actual work related to that was done by civil engineers, construction workers, and plumbers, rather than doctors. Still, it looks to me like the revolution in the 1935-1975 period that he talks about was only possible because of the improved understanding of the human body achieved in the 200-400 years before 1935.
Before 1935 doctors were basically useless. We had morphine for pain relief—a drug with superficial charm, at least—and we could do operations fairly cleanly, although with huge doses of anaesthetics, because we hadn’t yet sorted out well-targeted muscle-relaxant drugs. Then suddenly, between about 1935 and 1975, science poured out an almost constant stream of miracle cures. If you got TB in the 1920s, you died, pale and emaciated, in the style of a romantic poet. If you got TB in the 1970s, then in all likelihood you would live to a ripe old age. You might have to take rifampicin and isoniazid for months on end, and they’re not nice drugs, and the side-effects will make your eyeballs and wee go pink, but if all goes well you will live to see inventions unimaginable in your childhood.
It wasn’t just the drugs. Everything we associate with modern medicine happened in that time, and it was a barrage of miracles: kidney dialysis machines allowed people to live on despite losing two vital organs. Transplants brought people back from a death sentence. CT scanners could give three-dimensional images of the inside of a living person. Heart surgery rocketed forward. Almost every drug you’ve ever heard of was invented.
Perhaps what he means is the specific question of what your GP, personally, could do for you if you arrived at their place already ill?