The following link is to a blog by Ruben Verborgh, an academic and developer who works on Solid and LinkedData related projects, and met David along with Tim Berners-Lee at the dWeb submit where they were presenting Solid.
The following post is a great summary of the thinking that seems to be underlying the rollout of Solid by Inrupt (a VC backed business co-founded by Tim Berners-Lee) in collaboration with various government and commercial organisations.
Ruben describes what he sees as fundamental problems with the status quo and makes an economic argument for the replacement of this with user control of data, that he argues will lead naturally to many benefits for users, improved business models, efficiencies, and increased privacy.
I think most of this can apply equally well to either Safe or Solid. There are some significant differences but the key features are close enough that I think this article will help anyone understand some of the ways ownership and control of data can change the online landscape in Safe as well as Solid.
One question not raised in the article is the suitability of Linked Data (RDF) which we have debated here, but which Solid is built on and MaidSafe have been looking to incorporate in Safe at the API level, and possibly deeper.