The way I see it is that long game is to have agents in your life that memorize and understand your routine, facts, more and more. Imagine having an agent that knows about cars, and more specifically your car, when the checkups are due, when you washed it last time, etc., another one that knows more about your hobbies, another that knows more about your XYZ etc.
The more specific they are, the more accurate they typically are.
Do really understand deeply and in great amount I feel we would need models with changing weights and everyone would have their own so they could truly adjust to the user. Now we have have chunk of context that it may or may not use properly if it gets too long. But then again, how do we prevent it learning the wrong things if the weights are adjusting.