Following that reasoning, communism, capitalism and international trade are emphatically not part of Chinese culture - not to mention the way people in China now dress and most of the technology and consumer goods they use. Imperial monarchies interspersed with periods of civil war, economic and cultural isolation, and all of it based around Confucianism - that's been the culture since around 250 BCE, and they forcefully rejected Western trade and technology when they encountered it in the mid-19th century (leading to some horrible actions by the UK and other nations).
Chinese people in Taiwan and Hong Kong believe in and live these universal values, and they are the most prosperous, free, and stable regions of China. The values of freedom and democracy apply to other cultures worldwide, from Europe to India to China (Taiwan and Hong Kong) to Japan to South Korea to South Africa to Brazil. It's very hard to argue that they are just one nation's idiosyncrasy.
And who is to say that the people of mainland China don't want these things? Why not ask them? If Xi is so sure that a communist dictatorship has broad support, why not hold a vote?
Just saying that something isn't working doesn't mean there is a better option, either. Do you think there would be a different outcome if everyone pulled out of China completely and they do everything on their own without any external influence?
Yes I don't think that bowing to blatant censorship is a good option. He is enabling the suppression of free speech to make sure his stock doesn't drop. There are some cases where trading with China would be fine but selling products to wall off free speech is not one of them