Looking at the speeds with which people can communicate with Morse, I suspect that the skill of effectively turning your brain into a UART is something that improves with much practice.
Then I saw the frequency/time graph, and realised that didn’t seem to have been a consideration at all. This was obviously designed by a sighted person who cared more about what the pictures looked like!
Blind person: “But how do I know which letter is which?” Designer: “Oh, that’s easy! Just look at the picture!”
I love the idea of a sung language, though!
[0] As I was writing this I did have the wild thought that in theory if you had the weights already you could, in theory, implement a very basic character recognition neural net with analog circuitry using vacuum tubes that could recognize letters for direct mapping to sound but it's entirely impractical to create from scratch in reasonable time frames. Maybe over the span of decades you could manually tune one?
Kind of reminds me of Slow Scan TV - I feel like with enough practice, you could tell what the image looked like without using a decoder.
There are only 14 characters in that font - the digits 0-9 and four special field identification symbols. The 1970s "futuristic" text fonts which look like MICR symbols are purely decorative.
[1] https://en.wikipedia.org/wiki/Magnetic_ink_character_recogni...
[1] https://smartcheque.com.au/general-info/about-micr/micr-char...