Comment by viraptor

While the demographics non-overlap is true, it's not an insignificant number listening to him either. But he gets something else from Twitter: famous (verified) people involvement which amplifies what he's saying, and the profile being public to the world in a trivially news-embeddable form. I believe it matters and if he got a separate blog-like site where he can post, the reach and reuse of his posts would not be even close to what it is now. (and he'd possibly be less motivated without seeing the number of likes)