I see your point, but dash cams are recording the road, which is not a place that most people consider private.
An always-present personal recording device is different. People enter and leave areas that others feel are private. In some cases, there are even laws protecting what can be recorded (two-party states in the U.S. for example).
If something like these glasses started to take off, I would expect public backlash and legislation that restricted or prevented its use in certain contexts, which would essentially make them useless (the point is that you wear them all the time).
An always-present personal recording device is different. People enter and leave areas that others feel are private. In some cases, there are even laws protecting what can be recorded (two-party states in the U.S. for example).
If something like these glasses started to take off, I would expect public backlash and legislation that restricted or prevented its use in certain contexts, which would essentially make them useless (the point is that you wear them all the time).