i really like scratch, have started using this tool called pibakery that has a similar block-based interface: http://www.pibakery.org/
If nothing else, visual programming is of educational value
etc:
Seymour Papert's Logo maybe fits in somewhere here (source of turtle graphics)
sketchpad: https://www.youtube.com/watch?v=495nCzxM9PI
That being said, I think there may be a niche for visual programming tools when developing visual stuff. I'm old enough to remember Delphi, and also I made a few games in Flash back in the day. In both cases you would arrange visual elements, and you would attach stuff like event handlers written in a "real" programming language. I think the reason that it worked was that the visual part would be describing structure, not algorithms. In the same way that HTML is pretty good for describing UI elements without pretending to be a full fledged programming language. I'm not sure this division of labor would apply to Unity as well but I would presume so since it makes a lot of sense.
As for Scratch, I see it more as a real programming language but with a visual editor that makes it easy for beginners to compose programs by dragging and dropping. I think the tradeoff is great for beginners: makes the constructs visible and avoids syntax errors. I don't think it would scale to large projects, but that was never the point.
BTW, remember Logo from my school in the 1980s. I even seem to remember that we had the real, physical turtle at some point, able to draw lines on a sheet of paper. Or maybe my memory is deceiving me.
Having implemented, as part of my master's thesis, a program which would turn charts into code, and having since had the pleasure of working with several other ill conceived software products along the same line, I can only agree with Brooks. It hardly scales beyond the "Hello World" example which sold the idea to management. The only way to salvage anything from such a project is to commit any generated code of value and clean it up until it's maintainable.