I'm shocked so many people on HN support this. The only way I know to prove someone received a vaccine is for them to turn over their medical history. What if companies start refusing to hire someone because they have a bad medical history (insurance costs anyone)?
I'm sure many people will respond to this saying "they don't need to turn over their full medical history!" but once we turn over a part of it, they will want the next part, and the next, its inevitable. There will always be a safety and security justification.
And what of remote workers? A fully remote employee exposes zero company employees to risk. But they will be mandated to have a vaccine?
Why must we always lose one more right each day?
Edit: Apparently you receive proof of vaccination for the current COVID vaccines in the US. But isn't that still sharing part of your medical history? I have never once been asked a single question about my medical history during a job interview.