That wasn't my point. In fact, I agree with what you're saying.

But what happened with the covid vaccination was, firstly, that the State mandated it, either explicitly, or indirectly by discriminating against those who did not take it, including companies. The degree to which each of those happened depended on the jurisdiction.

Second, and more to the point that we're discussing, forget about the written contract then. There was no "and you will take experimental vaccines if I tell you so" condition of employment. So there had been no agreement, and unilaterally breaking an agreement is punishable, State or no State. In a free society, there would still be enforcement. In a variety of ways that can range from physical to merely reputational.

In any case, you cannot make an abstraction and move to the ideal libertarian scenario what happened to millions upon millions of real people in the actual conditions of 2020-2022. In those, the State is there to enforce contracts, and my position is that vaccine mandates are a flagrant breach that should be legally prosecutable. 

 We agree on both the premise and the fact that vaccine mandates are unethical.

But I will not argue that State intervention in company policy is a liberterian position.

I know this is an whataboutism, but most people are not applying the same principle with regards to Christian-owned companies refusing service/employment to homosexuals.

You could argue the scale and scope is different, sure, but the same principle is at stake. 

 I'm not saying that the state must mandate or not anything. I'm saying it must enforce contracts, which is its function currently, since we do not have a free society in which other non-State forms of enforcement would be available to those victimized. 

 That's a fair point 

 To concede your point to a significant extent:

It's true that one of the non-State options in a free society was available in the real scenario, as you said, namely not accepting the change of conditions, quitting (or accepting being fired, or not getting the job), and then taking to the public square to try to inflict a reputational punishment to the violators.

It's just that the effect of the State as the default enforcer over the real scenario is so large, that the result of the non-State option would be negligible compared to what it would be in a free society attuned to such mechanisms. 

 But relying on the State to either prevent or enforce company mandates is just perpetuating that power imbalance. 

 I think a scenario of non-mandates in either direction (pro- or anti-vaccines), with the state "just" as enforcer of contracts (verbal or written, doesn't matter) would be a huge improvement. I'm more of an anarchist myself, but many libertarians (minarchists, etc) would be happy with such status quo.