I think the headphone comparison is really weak. If you want to listen to any audio, in most settings you need headphones (at work, in public spaces).
Smart watches do not fill that void. They may make certain tasks easier, but there are other available options (like just pulling out your phone to look at the time or to see who is calling).
If you're wearing Beats (or any expensive headphone setup), it's not just because you need to listen to audio in a library or something -- you've made a decision to spend a considerable amount of money on a product with functionality that could be replaced, on most levels, for < 10 bucks.
I'm not saying there isn't a reason to buy quality headphones -- I spent like $80 on mine and love them -- but "nice headphones with noise-cancelling and extra padding and increased fidelity" doesn't seem like an outlandish comparison to "watch with extra stuff and it tells you the weather."
Smart watches do not fill that void. They may make certain tasks easier, but there are other available options (like just pulling out your phone to look at the time or to see who is calling).