Just a note that I don't think anyone is thinking of these watches as being for teenagers. They appear targeted at much younger kids, 8-11ish.
I'm sure there are plenty of parents who have given them smartphones and require their kids to always share their location with them, all the way through their teen years.
Yeah I think this is an important point and I think it is also worth adding that this is the same premise of 1984. Not that Winston (or anyone) is being specifically surveilled by a physical person at any given time, but rather that Big Brother __could__ be watching/listening at any time.
And it is important to also stress the difference in power dynamics between husband/wife and parent/child. These are apples and oranges; both round fruit but different categories at an important level. Like you said, the teen is learning who they are while a partner has already made significant strides in this direction and (hopefully) has already learned autonomy. Children must make mistakes, but the goal is to prevent large ones. Difference between getting a burn by touching the stove and catching oneself on fire.
As other posters have pointed out, no one really knows anything about anyone else’s life from an HN post.
That said, the whole point of the panopticon is that if the prisoner doesn’t know when they’re being observed, they’re effectively always observed. It’s a concern that’s at least worth giving serious consideration, not dismissing out of hand because it happens to work for you and your wife.