Every phone on the planet does this by default today. I don't see the delta between these glasses and someone taking a picture with their Pixel.
When phones first had cameras, and people were not aware, it would have been easier to secretly film. But news flash, where I’m sitting right now in a cafe full of tech workers, nobody would notice if I started secretly filming on my phone.
If I wanted to secretly film, I’d be more confident of getting away with it using my phone than with a set of glasses which have a flashing light on them.