My sense is Gutenberg tries to solve at least 3-4 obvious issues:

- beauty of UI
- ease of use
- the ability to create more complicated page layouts without knowing code (the same type of problem that page builders are currently solving)
- making extensions to the editor by themes or plugins more consistent at both code and interface levels

How well it does these things can be debated. Without any data to back it up, my sense it will do several of those things fairly well.

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I continue to believe, however, that the biggest looming potential calamity with Gutenberg will come from the fact that there appears to be very little concern for backwards compatibility or for the staggering variety of content that is created by WordPress users. They just haven't anticipated anything other than the most basic kind of content.

If Gutenberg is rolled in anything like its current form - which appears to be the intent, especially if there are considerations for a 2017 release - it will likely break millions of WordPress pages (those generated with page builders, tinymce-plugin content, custom post types, custom editing interfaces, etc, etc), and thousands of WordPress plugins and themes. The resulting chaos and uproar, as well as the damage done to perceived stability of the platform, could easily overwhelm any benefits.