Yeah I know someone who worked for a non-profit that helped H1B visa holders who needed an escape route from silicon valley jobs. They said companies would saddle them with doing shitty things that the engineers as a whole were generally resistant to. H1B holders are easier for companies to pressure because they have to leave the country if they quit and can’t find another company who will both hire them (with a job posting that’s compliant with the “demonstrate need to look outside the US” component) and deal with the visa paperwork administratively.

I don’t know anything about the medical and other folks here on the same visa though. I know my brother’s brain surgeon is on one.