India is known as the country with incredible potential but incredibly bad ability to achieve it. I used to think India was going to be the next big thing since I grew up in NYC and Indians were one of the very few groups of people who could academically challenge Chinese people but seeing how Indians in India actuall handle themselves, I'm no longer worried.
It is an observable trait in Australia has well. Indian typically perform exceptionally well like Chinese.
The difference in the big picture is that Chinese in China outperform diaspora Chinese (despite diaspora Chinese dominance in STEM and related industries in the West) while diaspora Indians outperform Indians in India by a wider margin.
Chinese who leave China quite often do so out of an unwillingness or inability to compete in China. At least this is often one of many motivating factors. Chinese diaspora who left in the mid to late 20th century (not trying to offend those here) are often lower performing Chinese and from more business minded regions of China - southern. Chinese students and technical experts who have left for the West to pursue high end academic and professional careers in the West are a fraction of the total migration, the vast majority of which do not represent much brain drain. Of the portion that do, many of these experts return to China at some point in their career/lives and often contribute again to China.
This just isn't quite as true for Indians. They do not return to India to advance their careers and contribute to India to anywhere near the same degree. This isn't because they have less loyalty or sense of nationalism, they do and nearly always emotionally exceed those of Chinese people. At some point we all recognise a material reason for this. India doesn't offer them the same living standards China does. Not even comparing India and China in the 1960s to 1990s where Chinese experts still returned not usually due to a sense of strong loyalty but because they are simply comfortable
enough in 1960s - 1990s China.
If one travels 3 months and broadly throughout the entire country for both India and China, there is simply no comparing the living standards of India to China. If China is benchmarked as a 10 (where the West on this scale would be greater), India would be a 3, at best overall. There may be pockets of India where these top tier Indian diaspora talents would feel comfortable enough, even very comfortable but it's just the rest that isn't cutting it for them. These people are often also India's "top tier" and feel very deserving of experiencing the hedonistic life whereas China has at the very least indoctrinated the slightest sense of socialism and confucian attitudes for accepting suffering (hard work) and being okay with living mid lives. Contrast with the Epstein class of western elites and where their hedonism is.