Old gatekeepers might not always have been worthy of praise, but at least there were a lot of them. And in that multiplicity there was the basis for democracy. In Amazon's vision of the future, there's just one gate. And while Jeff Bezos may wave everyone through, the health of the book business has already come to depend on the whims of one company. Even if he were a benevolent monopolist, that would be a terrifying process.
I think he misses the point a bit here--the problem isn't necessarily in the number, it's in the accountability. one gatekeeper could be a lot better than a million if that one isn't driven by desire for greater profits