then there was a significantly delayed improvement during Mao's reign of terror, and when he was sidelined due to illness in the 1970ties and capitalist policies adopted, China finally caught up to its peer counties.
You're misreading the data. The biggest step in the graph is from 1965 to 1970, full Maoism, and from 1970 to 1975 it's still during Mao. I explicitly said at the beginning that life went from 35 to 60 and you said that's false, you literally didn't know the data, and now you're moving the goalposts from "Maoism didn't increase life expectancy" to "maybe it did but less so than in South Korea".
As for why China developed slower than South Korea, South Korea is an American military base with a population of just a few tens of millions. It received humongous investments and tech transfer from the US as part of a specific policy. If you want to compare to something more akin to China, you could compare China to Indonesia or Philippines, which didn't receive the same amount of American resources. What does life expectancy and poverty reduction tell you there?
Mao delayed the improvements seen during that time all over the world
All over the world? South Korea is the exception. Look at life expectancy evolution in India, Philippines, Indonesia, Bangladesh or Pakistan, all countries with a much greater population than South Korea. China industrialised because of communism, there's a reason why it's more developed than any of the aforementioned countries even if it had a very similar starting point in the early 1900s.
Also, you really think that telling me "Dengism in China uplifted 800mn people from poverty" is an argument against communism? The communist party of China literally envisioned the policies necessary to attract the level of western investment to grow so fast, and managed to direct this investment in a way that would industrialise the country and not just exploit it as the west does in South America and Southeast Asia. It's the best example in history of poverty alleviation through conscious state policy. Dengism in China is not "capitalism", it's socialism with Chinese characteristics, and it's what allowed China to become arguably the most powerful country in the 21st century in a way that Europe and the US can't even begin to understand. I take it you're a supporter of the modern Communist Party of China, which enabled all of this?
Also: what a fucking anarchist, mate, defending the literally fascist dictatorship of South Korea up to 1990 as the growth model of a country. You're dirtying the name of anarchists, and I say it as a Marxist Leninist