Why the beatup and ‘outrage’ against these glasses of all things?

Presumably for the same reason people have disliked other secret/hidden cameras in the past.

How many times a day does someone have their mobile phone pointed at you, and you have no idea if they are taking photos or videos?

Exactly. They have it pointed at you. In other words, you are able to recognise that there is a camera there and that they may be filming. If someone walks into a public toilet or past a kindergarten wearing glasses, how would you know if they were recording? These glasses are designed to look like pretty standard consumer glasses and are difficult to recognise as smart devices from a distance. It also creates a problem where literally anyone wearing glasses in an area or situation where recording could be problematic becomes a suspect, even if they're just wearing normal glasses and have done nothing wrong.