This author confounds the principles in Flow which deal with how to individually optimize your experiences throughout your life including your work with what I call "The Joel Spolsky Flow" (not a dance move) which says that in order for developers to produce their best work, they need to have the opportunity to work uninterrupted for large portions of their day. These two concepts are orthogonal.

He also seems to think that a developer working in isolation won't have the judgement and ethical sensibility to understand what code is good for his employer/client. This is a massive fallacy in his own article that shows a certain bias. Any responsible developer can work either in flow or without and still produce code that is "good for business". Any irresponsible or immature developer can produce the exact opposite code regardless of flow.

As an aside, that book provided a fundamental shift in how I look at work. To boil its tenets down to "Flow makes you write sucky code" is to completely miss the point of the book in such a way as to appear disingenuous.