Programming “via” Visualization — doesn’t scale. Great for demos. Good in limited places. Visualizations “of” a Program — quite useful. Note there lots of different ways to visualize the same program to emphasise / omit different details. The map is not the territory, all models are wrong etc.
For example having models of capacitor and resistor you can put them together in schematic. Which in turn can be a part of the bigger design. Then test it in simulator. That's how Simplorer works. Alternatively you can write the code in VHDL or Modelica. But visual is quicker, easier, and more reliable.
Obviously it works well for UI, was used for decades now.
As for the rest,... there are visual programmers for robots, mostly for kids.