Pundit's a bit behind the curve
We've been prohibited from investing in Chinese tech companies for some time now. This latest turn of the screw, barring "US Persons" from working at companies or wherever else decreed by some Treasury official or another doesn't just affect Americans (and Permanent Residents - Green Card holders) from working at certain (any?) Chinese companies in the US but also at companies in China.
For a country that's always going on about how its "The Land Of The Free" we certainly put up with a lot of restrictions about where we can go, who we can work for and so on. Its very un-American but you'd need deep pockets to challenge the Federal government in court. As it stands I haven't a clue whether doing a particular job or not would fall foul of this week's diktat, all I know is that there's some official in the DC bureaucracy that's being paid to make a nuisance of him or her self who's on a bit of a roll these days. Someone please, please, stand up to them!
Incidentally, they've dropped the pretense of "national security". That particular fig leaf was getting a bit withered.