In reply to Tung.

I've long wondered if the trend toward page builders would do this to themes as well. With most modern page builders, often the best theme is more like a vanilla theme with little styling to interfere with the page builder generated pages and templates.

Basically each page has its own design, top to bottom, that overrides any theme styling anyways. Taken to its logical conclusion, themes would become obsolete.

That said, I don't have the impression that Gutenberg goes nearly as far in this direction.