It used to be the river was a fun place to hang out. Then more people started dumping their sewage into the river. At first it wasn't so bad, but over time it got worse. Finally, one turd became the last straw, so I looked for another river. Even worse! That's it. No more rivers for me. Nosiree Bob!
Twitter after the 2007 SXSWi was not considered a sewer, even with 140 characters. The River Fleet, in Roman times, was not a sewer. Most assuredly Twitter did not build their system as a sewer.
Twitter doubled its limit, so by your definition is no longer 'ideal'. The shitposting doesn't seem to be affected. Even if 140 is ideal, why should I think that unlimited length would somehow prevent problems?
I prefer to think you didn't think through the metaphor of your 'Executive Summary' well enough.
Only brought up Twitter because of original article. If you ask me, that entire industry--Twitter, Facebook, LinkedIn, etc--is a sewer, and always has been a sewer.
Whether it's social media, online games, or something entirely new, when there is a) real-time feedback, b) a profit motive, and c) a large enough user base to conduct experiments on, it is only a matter of time before someone gets the bright idea of hiring a few data scientists to optimize the rube-fleecing. Then it becomes Pavlov's human.
The whole awful business is the crack-pipe of our upper-middle class, and the guys who made those crack pipes knew exactly what they were doing. If a bunch of alt-right shitposters shoved Wil Wheaton off of the pipe, they unintentionally did him a favor.
And as far as original analogy went, sewers were designed for sewage. Rivers weren't. It is not that complicated.
Wheaton did not refer to early Twitter as a sewer. That's why my comment points out that your "executive summary" is a misnomer. It is your interpretation. It may even be a correct interpretation. But it is not an accurate summary of what Wheaton wrote.