I agree with you. U.S. optimism is definitely one of its defining traits, which is in part a function of its history and geographic location (Europeans have good reason to be much more cynical and "realistic" about their place in the world, how much they can truly accomplish, etc.). And that certainly places a higher ceiling on potential innovations. But tied into that is the popular belief that the "free" market should be allowed free reign so that the U.S. citizenry can properly take advantage of these opportunities. And that means lower taxes than other places in the world, and fewer social supports. Which leads to less of a focus on public education and public health, and in turn, to fewer macroeconomic prospects. Many don't seem to realize this dilemma, unfortunately.
As for China, I do agree that more "in the box" thinking takes place there, which has pros and cons. If you look at graduate enrollment in U.S. universities (globally recognized as among the very best in the world), there are extremely high rates of Chinese (and Indian) enrollment in the sciences and engineering. This is a result of what you're talking about, because the government and families are pushing kids into STEM (science, tech., engineering, math) fields of study. But most of these students don't have ambitions of being the next Bill Gates. They just want a comfortable living, and they can get that by devoting their professional lives to this kind of work. In the U.S., there's much less of that kind of push, but on the other hand, we have ambitious kids who want to run large businesses, who want to change government in fundamental ways, and who want to not only live well, but to become wealthy and powerful.