I think the disconnect here is that we are talking about two different kinds of success.
@Hendrik_2000 and @Tse are referring to personal success, where one makes money, provides for their family, and maybe build some legacy for the kids.
@taxiya, @plawolf, and I are talking about national success, which is a different matter altogether.
Yes, I would agree that in personal success, the culture of overseas Chinese plays a big part. We value education, good work ethics and familial bonds, which allows us to achieve financial success over generations. However, personal success does not necessarily translate into national success. Just because our culture enable us to do well as immigrants, does not mean that same culture will necessarily make China, as a nation, succeed.
I can understand that, as immigrants whose family left China before the founding of the PRC, some of you may not be very familiar with the developmental path of modern China, but I can assure you, China's success today is built not upon culture, but upon policy.
First is the policy of land reforms. While it did lead to the great famine of the 60's, it also empowered hundreds of millions of Chinese who previously lived under the whims and mercies of their landlords. This empowerment allowed the creation of a vision, THE vision, of a modern China where everyone is equal. It might sound trite and cliché today, but in 1949, it was an utopian dream. Without this vision, modern China would not have been possible. This was what Sun Zhongshan sought to achieve, but he never succeeded in spreading this vision beyond the intelligentsia. Mao's greatest contribution to Chinese history is the spread of this vision to every Chinese citizen, and it would not have been possible without those land reforms.
Second is the policy of "Two Bombs and one Satellite". In the deepest throes of the Cultural Revolution, the government decided to pursue these three highly ambitious scientific programs. The success of these programs assured China's military security, and kickstarted China's scientific expertise. In only 10 years, China went from digging in the dirt to sending satellites into space!
Third is the policy of market reform initiated by Deng Xiaoping. I believe we are all familiar with its results, and I needn't explain those further.
Those are just the major, landmark, policies. Aside from them, there are countless smaller policies and initiatives that built China into what it is today. It was not Chinese culture that initiated and then implemented these policies, it was the existence of a strong, central authority, and the support and belief of an empowered Chinese population.
I would just tweak it a little to say that Sun Zhongshan, the Nationalists, select warlords, reformers, activists, and rebels of many stripes from the late-Qing onwards contributed more to today's China's success than you give them credit for. China needed so much practical change that it took all these varied Chinese people all that time and effort to facilitate the situation to be workable for the Communists to eventually successfully carry out their part of the needed change for China, notwithstanding the conflicts among all these groups. Chinese culture and identity is the underlying unifying factor throughout that ongoing process.