You could make the case that "stealing" talent is in terms of targeting hiring people where the training and research costs were footed by someone else.
Then again, as you pointed out, you could also make the case that they weren't properly compensated.
In Moscow, major Asian companies like Samsung, Huawei, LG all have research centers where they hire some of the best science students from top universities, in particular by organizing joint study programs. This seems to be a widespread practice around the world for them, and actually profitable for both students and universities.
Interesting observation about Moscow having a lot of research labs. I never thought to wonder why Moscow had so many but this is an interesting point. What do you mean by join study program? Can you explain? Also, is there anything that stops top talent from moving to Silicon Valley (or some place else?) after they finish school?
Many top universities here are not like self-contained research universities of the West — they mostly deal with education, and research is conducted at non-educational academic institutions. So, for their Masters work, and maybe earlier, students do research in various organizations that have contracts with university. These are either academic institutions or commercial research departments or tech companies like Yandex.
As for SV, it’s not that simple, it seems — most emigrants that I know either got job at something like Swiss Google after building a solid resume here or got into some academic program (PhD or postdoc) abroad.
Sometimes, paying people well goes hand in hand with opportunities for growth. The "bamboo ceiling," which is similar to the "glass ceiling" is a source of frustration for some technical employees who find themselves stuck.
Diversity and inclusion programs at most companies tend to focus on every demographic bias except for the bamboo ceiling.
