Thanks for the Tennenhouse link, definitely ahead of his time on Proactive Computing. You're right that 'Post-Interface' is a rhetorical hook. We can't eliminate the technical interface (APIs/protocols). My argument is about eliminating the cognitive interface for the end user. Right now, even our smartest agents are still reactive because they wait for a prompt. I see generative UI as the bridge to true proactivity: instead of a static dashboard waiting for input, the system constructs a temporary UI only when it senses intent via context/API. The goal isn't no interface, but zero friction interface where the UI is a generated byproduct of the agent's action, not a prerequisite for it.