I'm basing that off a book I read which described how the original liberators of South America (who were mainly locals, not from the Spanish or Portuguese elite who ruled) were heavily influenced by these (mainly French and English) liberal European thinkers - which is why they wanted a revolution in the first placed. It didn't come from local culture.

The Spanish did not create liberal "western" democracies when they ruled. They were replacing a monarchical, heavily centralized system and the liberators had a choice in how they modelled their country. They certainly considered many different options including heavily centralized systems but the influences of European thinkers as mentioned above played a big role in their decision to build republics and federalized states.

My point is that many cultures (including Japan and South Korea) came from a legacy of centralized control and were still capable of being inspired by foreign thinkers and adopting liberal systems.

This idea that China is unique because they didn't have their own bastion of local liberal thinkers is heavily flawed because that pattern exists elsewhere with different outcomes. Especially considering how close Chiang-kai Shek was to moving China towards a more western economic system. It wasn't the 'Chinese way' that won out, it was a series of politically fortunate events in Mao's favour.

The Chinese culture is a product of a self-protecting centralized system, not (merely) a product of the historical culture.

The political and social culture of South America, at the time of their wars of independence, was undeniably based on European culture and values, at least among the educated classes that actively participated in all that. Their blood descent is not particularly relevant - what matters is the kind of books they grew up with, roughly speaking.

I don't think that japan and south korea fits too well in here japan was ruled by america in the years after the second world war, which is where a lot of the modern thinking is coming from. And I belive that similar thing have been happening in south korea, but I am not too sure of that.