Intrusion into issues that should be private.
More government control over movements and activities that we don't need.
Creates two classes of citizens.
Those will go to start with, there's lots more.
A lot of what folks think about that depends on what they believe from the state about viruses, efficacy of vaccines, and what control government should have over citizens. What's next, an "anti-racist" card? A card saying that you agree with the current administration? Once they know that you'll stand still for this, there'll be no end to it ...
Won't fly here.