A tourist visa does not permit someone to work legally in China. And Chinese companies do not hire foreigners so the point is moot: there are more non-native Chinese people working in Silicon Valley than foreigners working in all of the Chinese tech companies in China.
Your examples prove the point. 3M is a manufacturing company that distributes face masks. Microsoft collects payments because diplomatic pressure from the US coerced China into paying for software licenses. And Yahoo stopped being active in any meaningful way more than a decade ago: their Chinese search engine even redirects to Singapore. All three companies are also effectively guaranteed to have more Chinese hires working overseas than foreign staff working in China.
Like it or not, the bias against China is easy to understand: China is racist and non-meritocratic in ways that Western economies are not. Tech workers face harsh wage competition (from Chinese workers) and commercial competition (from ventures with direct or indirect state backing) without any countervailing upside (the ability to compete in the Chinese market or play off Chinese against American employers).