Even then, sites which lack graceful degradation aren't so qualitatively different from the few that do that they need to be moved to an entirely different platform, viewed from a different device and considered "applications" and not "documents." That seems like throwing the baby out with the bathwater.

What does make sense to me is a new platform based on WASM, with related tooling. Photoshop in the browser or something running the Unreal Engine or .Net is not the web enough to maybe deserve its own thing. But a new platform based on what are essentially complaints about complexity or efficiency would be too messy.