My observation is that it actually accelerated said brain-gain.
There was a crackdown on fraudulent H1B applications, with more RFEs being issued. That freed a lot of spots for legitimate applicants that were hogged by questionable bodyshops. It also incentivized attorneys to start looking at O-1 (and they are easier than people think for real engineers to get).
Academically, a lot was written (by foreign universities) about how the US was going to lose it's edge have a drop in applicants but the rankings didn't change during the last 4 years. I wouldn't be surprised if more people applied simply because they (erroneously) believed that admission would be a little less competitive with less applicants.
This is misleading though, because a majority of H1b applications are renewals (so folks already on an H1b), not new applications. On top of that, most renewals happen to be Indian Nationals because they have no pathway to obtain permanent residency in many cases.
Also how does a higher rejection rate lead to brain gain? I'd imagine it discourages a would be immigrant.
Curious what you're implying happened in the US in the last 4 years. Maybe I'm missing some important event other than Covid but that affects all countries.
There was a crackdown on fraudulent H1B applications, with more RFEs being issued. That freed a lot of spots for legitimate applicants that were hogged by questionable bodyshops. It also incentivized attorneys to start looking at O-1 (and they are easier than people think for real engineers to get).
Academically, a lot was written (by foreign universities) about how the US was going to lose it's edge have a drop in applicants but the rankings didn't change during the last 4 years. I wouldn't be surprised if more people applied simply because they (erroneously) believed that admission would be a little less competitive with less applicants.