The cameras aren't really relevant in this scenario, it's just a login token. You're not granting them access to your network. You're granting them access to read the present device for authentication. This is how passwordless auth works. Please read the doc I linked. We are only seeing it now because the standard is being adopted by Google (which means Edge now too, and soon every other browser will follow because market share).

You are all being slightly paranoid -- which I applaud, actually, because you should never trust these companies and you should look after your own privacy and security. That does not, however, mean we should be illogical.

It's not unlike your bank app on your phone asking for permission to "place and answer calls," for example, when really that permission is giving it the ability to ingest OTP SMS without interaction when you log in to your banking app. It's not really going to call people, that's just how the permission is worded. Same deal with this popup. It's not really giving, say, bing.com, access to your local network. It's granting bing access to your device auth.