Would this approach work for these camera glasses as well, simply flooding them with so much IR spectrum light that their sensors simply can't see you anymore?
I think fooling facial recognition systems and CCTV-cameras-at-night is easier than fooling professional photographers. Most photograhers' cameras have IR filters, after all. And nobody's got an LED brighter than the sun.
It's low density silly fun but I did see these folk attempt to do such a thing with entertaining results https://youtu.be/m1S1r9I6DN4
Of course it is a different thing if these are adopted by the masses
You could train a system to detect these kinds of attacks, but that's a lot more sophistication that these types of systems usually have, and would probably be specific to each "attack" (e.g. those glasses with lights would look completely different than the face paint approach)
The best defense would be a human watching the raw camera feed, since most of these attacks are very obvious to the human eye. But that's expensive. Maybe you could leverage vision-llms, but those are much more expensive than dedicated face-detection or object classification models. Those typically range from sub-million to maybe a hundred million parameters, while you need billions of parameters for a good vision-llm
Perhaps combined with some reflective coating? Retroreflectors are promising