maybe if the author swings by:

The Doom 2016 soundtrack contained a spectrogram image; and

with RF you can transmit images in the same fashion. I am ~80% sure that fldigi can do it, but if not, there's other open source software that can do it as well. And this isn't like hellschreiber, it looks like the spectrogram images on the RF spectrogram. The images don't "go" as far as dedicated digital modes but it's still kinda fun to mess with people in your area (like within 100 miles or so, depending on band, time of day, and E[i]RP).

Here's a high resolution version. 2 MHz wide OFDM.

https://www.youtube.com/watch?v=saac0ZtTeX4

https://github.com/drmpeg/gr-paint

Man, that is something I haven’t thought about in over two decades. I remember that circulating around early aughts internet. And I think there’s something to your theory.