Ironic that he talks about Leadership, hindered by a lack of diversity, has steered away from a tool for public good and one that is instead subject to capitalist forces resulting in monopolisation in Medium, a company that also tries to monopolize and capitalize the blog’s information
Platforms actually have one significant advantage over personal websites, blogs, disconnected forums: You only have to go to one website (open one app) in order to read everything you find interesting. You don't have to remember to go to 5 different forums and read 15 different blogs.
Of course the disadvantage is that they are a lot easier to censor because they're a single point of failure.
ActivityPub should in theory be the best of both worlds, but I am not too optimistic; people, organizations, governments wanting to censor people they don't like will always find a way. :(
So? He stays pretty busy with Solid / Inrupt and his other advocacy (e.g., the OP article...)
Perhaps he sees the personal blog format as a bit egotistical or otherwise not fit for purpose. Or perhaps he just isn't a naturally talented writer. Its not as if he's shy about sharing his thoughts outside that.
Also worth noting that he and Bruce Schneier, who is a much more prolific writer, share many of the same views and partner together at Inrupt.