The points about centralized power make sense, but why http, smtp, and social media became centralized in the first place wasn’t grappled with at all. Running your own servers is attractive for some, but they aren’t the majority and never will be unless it requires something as simple as buying a $35 box and plugging it in at home with no additional setup. Social media is hard to accomplish without a centralized disc…
Also, Wikipedia has shown that centralization is necessary sometimes. For example, political pages are frequently locked because people with the most extreme and inaccurate viewpoints are the most vocal.