In other words, imagine that instead of being forced to digest a plurality of static and unforgiving view hierarchies from designers on high, you have with a single, long-lived, personalized UI that is flexible, changes with your needs, and allows you to integrate new data and services alongside or into existing workflows. Think of it as a personal UI agent.
I like this model of software primarily because of how much creative power and agency it gives end users. "B2C" could end in "creator" instead of "consumer". It's unix-y in its composable nature, and more in line with the hopes we had for the web's ability to unlock creativity in its infancy.
It also seems like a step towards a world where we see fewer ads, because there's more of a culture of paying for digital products by usage or subscription (though ad-supported options would remain; I don't see this as a revolution against ad-supported models).
Obviously, lots of challenges to execution, but would love to hear of anyone else thinking along these lines!