You could even create dynamic routes that changed color while you were climbing them, or perhaps only showed you the next two holds you could grab, so you wouldn’t know where the route ended until you were near the top. Both would require weight sensors on/in the holds though.

P.S. Note in the photo you included above that they use all holds of a certain color to indicate a route, rather than tape on the holds. I prefer the tape on the holds technique as it allows for many more overlapping routes to be tightly packed into a smaller set of holds and area of wall, though the colored holds path is more common.