Uncle Bob fooled many developers to join his sect. I am much happier since I've discovered that there's not only "one true path" and OOP, SOLID and Clean Code are not the means to everything in software.
He makes money whenever he convinces someone he's right, of course he's convinced many to join his sect.
This post is not related to Uncle Bob's book, which is not even mentioned. The term "clean" here is subjectively interpreted by the writer of the post.
It's ambiguous really. Clean architecture refers to architecture that is structured in such a way (mostly by relying on tests) that one can "clean" out crufty portions of the code and not feel anxiety because one's tests should give one peace of mind. Whether or not the author was referring to the clean code as part of a larger clean architecture or just that the code wasn't crufty in general isn't clear. I would have preferred that the author used a different term (or that Uncle Bob had chosen something less common himself).