The idea that you should expect to be searched to enter concerts and sporting events is more insane. And yet that's just been the new normal for the past 15 years.

The biggest issue is whether businesses can use your personal information for purposes other than checking vaccination status.

Some of the European systems I've read about seem to discourage that, and the GDPR would also seem to prohibit it. But there's no willpower for such laws in the US, so we'd inevitably end up with the synergy of government and corporate power, like everything else. For instance, half the surveillance systems I listed in my other comment rely on abusing government-mandated identifiers.

Yeah, but that new normal isn't really desirable in itself...

I never said that it was, which was apparent from my characterization of "insane". I was merely pointing out that framing vaccination requirements as some sort of watershed totalitarianism is ridiculous. We get far less specific benefit from other intrusions. For example, spending the political energy putting surveillance valley out of business would go much further for freedom's sake.