I owned smartwatch now for nearly 2 years, a Sony SW3 and a LG Watch Urbane 2 LTE.
The core problem is size vs battery life. The smarter it is the more it needs taking off and recharging. The Sony once it was tuned would last >24h so you put on charge at night or when in shower and worked ok but it only really did notifications filtering, good for glancing at wrist rather picking up phone. The LTE watch, well when I used it standalone on LTE, lasts 4 hours, so that's for some activities like jogging when paired with some BT buds if someone phones you then you can speak without taking a phone, but severely limits other use cases.
Then there's this problem given you squeezed it to a small item and put on a warm body:
So what happened was that smarter watch made itself too ambitious and its on a shelf not used and I use the less-smart Sony still more often when moving a lot with phone in a pocket and BT buds paired to phone.
We need an order of magnitude improvement in electronics, performance per Watt. That will take years.