I remember seeing some celebrities in the late 00s / early 10s with IR-emitting sunglasses or accessories to flood the camera sensors of paparazzi and make it harder for photographers to get spyshots of them.

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?

One of my future ideas was to have the detection trigger turning a bunch of IR LEDs on to do just this! I've only tested it a little bit against my phone camera (with around 5 850nm LEDs), but it didn't work super well (fairly bright but not enough to be useful). It did work much better in low-light though. My guess is modern cameras have better IR-cut filters, but like I mentioned I only tested against my phone and not the Ray-bans yet.

Well, there's https://www.nii.ac.jp/userimg/press_details_20121212.pdf

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.

What about correlating transmitted wireless frames with a LED flashing pattern? If the glasses stream video with a variable bitrate codec over wireless, flashing vs. non-flashing should change bandwidth and therefore frame frequency. However, with searching over all channels this might be quite slow in practice.

I have been thinking of a device to thwart license plate readers by dumping a ton of IR and/or visible light on the plate before it gets read.

Perhaps combined with some reflective coating? Retroreflectors are promising

I heard about similar hats being used during the Hong Kong protests, but most modern cameras filter out IR anyway. Reflective jackets tend to work much better; they basically turn you into an overexposed bright blob on camera.