You don't know if it's being watched or not, you don't know if its event triggered or always-on, or how anything you say and do is contextualised. You only know it may be used against you at any time.
What it crystallises for me is the implicit "if you are pure you have nothing to fear" quality in these things. The idea that the loss of privacy is inhibiting and that this kind of law is antithetical to a fundamental expectation of privacy as a right. Many places have no written constitutional norms in this space, and so the right to privacy is assumed, not codified. (and, it would be equally simplistic to assume codified rights necessarily enshrine them or strengthen them)
The thing with real-world effects is that the channel to control this would be their ability to constrain IR shielding materials in the supply chain. But if they were ubiquitous, then I guess it's a good analogue: you would be guilty of the crime of attempting to hide your IR signature, not of any specific act done under the banner of being IR invisible.