And it sucks.
It sucks exactly for the reasons in the article. It sounds great and looks great for simple processes. But that isn't the reality of approval processes and integrating with existing systems. The complexity of these "visual" workflows grows exponentially with the complexity of the real process. Complex to the point where it can no longer be easily tweaked and maintained by the original designers/maintainers much less the client.
Yes, there are some systems that apparently work great: visual effects (which sounds much more functional (in the programming sense) than real world programming), and Scratch: to help kids make games. Scratch is inherently simple and I bet if you asked someone who has a history in programming what it is like to scale a program up in Scratch, you find the same thing. That it starts off great, but as complexity of requirements increase linearly, complexity of the "program" increases logarithmically. That they wish they could just port it to something like Python or at the very least, embed a language in it.
(Side note: I wonder if this says something about (natural) language as well. No natural language looks like a visual workflow. Not even hieroglyphics. You gain much more expressiveness and flexibility by the simplicity of the concepts. It doesn't get much simpler than a single linear string of words. And I think programming languages gain the same expressiveness and flexibility by having those characteristics.)