The author expresses hope that one day it will be the Apple of Android world and I also think that it will happen one day. You should consider the pixel watch as the first MVP (first iteration). It will take serveral iterations to come up with a truly classy product.
Hopefully, the collaboration between Google and Samsung will also improve further.
Difficult to comment on integrations as it is also upto the 3rd party developers to make the apps available. But surely, with newer versions of Wear OS and as more and more companies switch to Wear OS for their watches, the eco system could get better, at least thats the hope.