China is a different story, let's exclude that.

India's requirement is 12 years seems a lot, but practically Indian citizen's path to citizenship in US is more than that(~10 years to get GC + mandatory 5 years after GC). EB1 might be an exception, which will also come around 6-8 years. But most end up waiting more than 15 years to become US citizens.

US restricts employment visas with a specific time limit. L1(7 years) and H1(6 years). After that period, you have to stay out of the country for 12 months, before you can reapply again. The other option is to apply for Green Card (Permanent Residency). So most of them end up applying GC rather than move out of the country for an year.

US has weird rules that inherently makes difficult even for employment based visas. E.g. If your visa is near expiry, then you can apply for extension. But the extension processing times takes up months. You can't travel out of the country during that period. Even if your petition is approved, then you have to go to US embassy in your country of citizenship to get visa stamped in your passport. Unless you have a visa stamped in your passport, you can't reenter US. Practically there is no visa appointment slots available at US embassies in India at this time. You are in a soup if you have to travel on an emergency

https://twitter.com/debarghya_das/status/1520966725210042368

https://twitter.com/USAndChennai/status/1517067638584664064

If a foreigner works in India on an employment visa, I don't think they have to run into issues what someone faces with the US immigration system. Just see what Curl's author Daniel Stenberg experience with US Visa process,

https://daniel.haxx.se/us-visa.html

user:	saravanannkl
created:	April 19, 2016
karma:	11