Wow yeah, there's no other way to take pictures or listen to music with environmental pass-through

Taking pictures of small kids is a different thing altogether.

Many of the shots you want are very fleeting moments that you won't get after you took your phone from the other room. Then holding a phone will often redirect attention on the phone or hide your face, and again you'll have lost the moment.

The best alternative is someone else taking the picture (that can include auto photographing devices, like the one Google made and discontinued), the second best is you taking the pictures/videos with the most intrusive and practical device you can get. Smart glasses sound pretty good for that.

On the music part, I see a niche where glasses are unbeatable: most buds need to either stick into the ear canal or hook on the external ear, or both. If you hate things in your ears and also wear glasses, having the glass act as headphones is the best of both world.

None of that is mainstream IMHO, but there will be a sizeable public clamouring for these.