Memes

US life expectancy in 1940 was 62, almost double that of China. The state of medical knowledge and technology doesn't matter if the people don't have access to it, as was the case with many Chinese, especially rural people. What actually made up a large part of the difference was not antibiotics but vaccines, which were around well before WWII, but Chinese people had virtually no access to them. Under Mao, China implemented something called the Barefoot Doctors program, through which large numbers of doctors were trained quickly and sent out to rural regions, relying primarily on Western medical knowledge, though they also used some traditional herbal remedies due to the massive amount of medical supplies needed to expand care across all of China. The program was a success and resulted in the sharp rise around 1968, when it was implemented.

Another factor was land reform and increasing food security. Yes, the GLF was a failure, but before the communists came to power, famines were an extremely common occurrance. Rural Chinese were suffering under extreme poverty and brutal exploitation under the landlords (really more like fuedal lords), and the communist uprising redistributed the land which allowed farmers to keep more of what they produced.

Generally, there were a lot of improvements in the lives of rural Chinese that were very basic and obvious. Anyone who went and observed their conditions could plainly see things that needed to be changed. But no other faction - the KMT, the invading Japanese, the European colonizers, the Qing, etc, hell even the communist party before Mao wasn't interested in trying to reach them, as I mentioned. The reason Mao got so much support from them, and the reason that he knew they could be radicalized, is because he actually took the effort to go out and live among them and listen and learn about what their lives were like.

Those reasons are why, despite the failure of the GLF (which we can discuss if you like), I would still argue that there have been a lot of material improvements for the people of China which wouldn't have happened under any historical faction but the communists. Notably, Chinese life expectancy has now surpassed that of the US, while China has emerged as a major economic and geopolitical power, despite having once been one of the poorest countries in the world.