It's always wiser to not speak in absolutes about what Apple may or may not be experimenting with. They've gone their own way too many times in the past to ignore.
As to the people wondering about whether or not watches are still prevalent - you need to pay more attention to your surroundings, instead of spending all of your time hunched over your phones or fishing around for them in your pockets! :) As some others have noted, business people, medical professionals, engineers, all sorts of professional types still use watches.
I've worn a watch ever since I was in high school, back in the 1970's. The one I have now is very handy - solar-powered, syncs itself with NIST Atomic Clock every morning around 2:00 AM, so I never have to worry about setting it.
If this theoretical product ever sees the light of day, I suspect it would follow the usual path of Apple releases: panning by pundits, then bought by the people who are too busy to worry about what other people think they should purchase. I could easily see something like this being used in conjunction with an iPhone, iPad or iMac for screening and taking calls, using Siri for quick texts and queries, handy GPS mapping for local routes... If it used the latest low-power Bluetooth for syncing, its battery might be manageable. Who knows? Fun speculating, though :)