It's like treating concealed carry of a weapon differently than open carry. I think it's reasonable to say "you can do this in public but only if it's clear to other people that you're doing it".

Targeting smart glasses specifically seems to narrow though, because there are obviously many other ways to carry around a hidden camera in public, like one disguised as a pen in your pocket or something.

I think it's because it's more plainly obvious if someone is taking photo if they're lifting up a phone to do it. Someone taking a photo with glasses can be done more covertly.

It’s easy to see if someone has a phone or camera pointed at you. If someone’s looking in your direction while wearing glasses, you would not typically expect them to be recording you.

There's a big difference between holding up a phone and taking a picture and just... existing with glasses and having everything recorded without your knowledge.

People care more about the illusion of privacy than actual privacy itself.

Even if we banned smart glasses, we'd still see ever-expanding networks of privately owned cameras that record every movement you make. We'd still have networks of ring cameras and similar devices. We'll still have ever-increasing use of AI to sort and categorise the content.

Privacy is dead. Smart glasses are just an uncomfortable reminder of this fact, and banning them without addressing the over-arching issue is similar to sticking our collective head in the sand.

I don't understand how this question can be asked in good faith?

If you have to defend smart glasses based on a technicality, that doesn't reflect very well on the glasses.

Smart glasses that were clearly designed and visible were odious and shunned, so Meta (et al) have developed covert designs instead.

It's the same as a buttonhole camera used for spying. The differentiator (vs a phone or SLR or similar) is that its primary function is concealed.