Summary at Tyler Cowen’s blog:
But what does this new, more intense celebrity culture mean for actual outcomes? The more power and influence that individual communicators wield over public opinion, the harder it will be for a sitting president to get things done. (The best option, see above, will be to make your case and engage your adversaries on social media.) The harder it will be for an aspirant party to put forward a coherent, predictable and actionable political program.
Finally, the issues that are easier to express on social media will become the more important ones. Technocratic dreams will fade, and fiery rhetoric and identity politics will rule the day. And if you think this is the political world we’re already living in, rest assured: It’s just barely gotten started.
See also my post freedom, the village, and social media.