The idea is it reflects IR and blows out the exposure.

It kind of has a red tinted layer which creates red blobs in quite a lot of different lighting conditions. Even with non IR photography, if you are standing outside or under bright lights there's a good chance any pictures will end up with red artifacts in the lenses, partially or completely obscuring your eyes.

Videos testing these glasses show that face-id doesn't work when wearing them. This demonstrates that (at least for Apple), covering your eye area is enough to defeat IR-based facial recognition.