The title feels pretty clickbaity. I might be missing something, but this feels like another distributed annotation system for the web, an idea that's been tried and retried for what feels like decades a this point. Why will this one work when the other attempts didn't? Is it just about this being more restricted than those past systems?
(The example that came to mind first was Google Sidewiki, but it looks like there's a bunch of these listed in https://en.wikipedia.org/wiki/Web_annotation)