This is how I use my watch. Pretty much strictly for push notifications. I think people who thought the apps would lead the way are the ones who are most disappointed. I use notifications, the fitness app, and the hue app for my lights. I personally find all other apps to be pretty slow and a waste. The ESPN app is awful. In the time it takes to update, I could have looked at scores for every sport on my phone.
I am finding that people who came from a different smartwatch are loving it, and people who this is the first smartwatch are having buyers remorse.
I don't think it's quite that clear cut. I didn't own a "smart watch" before and didn't give it much thought before the Apple Watch. I did have a regular watch, though. I agree that those who wanted to use lots and lots of apps are likely the most disappointed, but seeing as we're talking about a 1.5" screen and don't even have native apps yet, I wasn't expecting much. The best apps will be those that do one or two things really well. Opening a hotel door instead of fumbling with a card key (that I tend to misplace) could be one example. Weather takes a while to load up at first, but after that it's fine. The watch face complications and notifications are the best parts.
Watch and use it in that kind of manner, then maybe it isn't for you.