I wonder if he actively realizes that the persuaders on Social Media are inevitably for sale to the highest bidder (albiet with veto power over things they may actually care about)? [I know how much it costs for Martha Stewart to send a tweet about your business... I don't love this world we live in.]

I'm reading between the lines, but I don't think he's advocating for social media becoming the government. I think he thinks he's merely observing what's already happening.

He writes a lot about Trump, but he explicitly says that he could deal with any of the current candidates becoming President. I have wondered if his logic is basically "Social Media is becoming the President no matter what so what 'meat robot' slots to the seat behind the desk in the Oval Office in matters little by comparison".

If you mean that it could in fact be worse than what we have now, you could model what we have now as still being essentially "media" driven, but with no way for anybody to break in the way social media does let some people now. Whether that's really a serious change once corporations do their second-order adjustments... dunno. I expect to still be chewing on these ideas for another few weeks.