I’m thinking it could be active enough to actually obscure the camera recording in real time whenever you are in the frame, like an actual beam that goes into the camera lens making the normal light intake all distorted, so it wouldn’t appear to malfunction or fail, it would just be like a refracting smudge in the feed.

I know these below existed, but it only works against IR enabled cameras aka CCTV, but definitely they won’t against smart glasses, but I love your idea, a glass distort the lights, hmmm maybe emit IR?

https://www.reflectacles.com/order/ghost