I don’t think it’s the CoC committee overreacting. I would reach to HR advising termination if a member of my team did this to someone in writing. This is straight up illegal in my country. If you write this to someone, you will lose if they sue. A lenient sanction and some probation seems fine for someone with a history of good contribution but doing nothing would be wrong.
I’m not sure comparing that to the NKVD is wise.