I don't think visual necessarily implies non-textual. I remember once seeing an old terminal app used by an airline that would allow you to escape the bounds of the input area if you used the arrow keys. You could literally type anywhere on the terminal which as you'd expect, effectively trashed the session till it was reset.

The analogy I'd draw is that programming in most editors is like that terminal app, you can do anything even if it's totally illogical and breaks horribly. When I read the question posed at the end of the article, the image that came to mind wasn't a pointy-clicky diagram monstrosity but more of an Intellisense with a tight input guard and strong visual delineation of blocks; a Python with even tighter structural rules rather than a UML on steroids.