Anything that resembles, anything that could be a precursor of the ‘The Mark’ needs to be resisted.
The line is that we have the right to peacefully, legally decline and not be threatened with violence, which includes theft, or other public institutional-based discrimination.

Remember ‘show me your papers’ from history.
It never ends well.

Employers have interest in knowing whether you’ve been vaccinated, as do the countries you want to visit.

Source: Why Americans will demand to be able to prove they’re vaccinated