The US didn't mandate deletion of their Github account. The US isn't punishing them – you can tell because they didn't put them explicitly on the SDN list.
Microsoft made the choice to remove their accounts. Their compliance team likely looked and said "$ we make from these devs < $$$ we'd pay to our lawyers to simply decide if we should keep them on our platform."
The US didn't mandate deletion of their Github account. The US isn't punishing them – you can tell because they didn't put them explicitly on the SDN list.
Microsoft made the choice to remove their accounts. Their compliance team likely looked and said "$ we make from these devs < $$$ we'd pay to our lawyers to simply decide if we should keep them on our platform."