The idea of having AI in browsers (see the "Application Use Cases") seems cool, but on the other hand, the idea of downloading & storing large models for each website/webapp seems terrible.

It seems to me that it would make more sense to have models built into browsers, and to have a web API that provides standardized ways to interact with the underlying models of each browser. From what I have understood from the WebNN spec, though, despite listing out all of the cool use-cases, the API doesn't seem intended to provide higher level functionality than loading, running & performing operations on a model.

Is my understanding of the API right, or is there something else that uses it to make these use-cases available in browsers?