Why aren’t dynamic phone ringtones more mainstream?

Considering that we are being yelled at by electronic devices at a high rate, why don't we have dynamic, synthesized notification sounds in our electronic devices?

Our brains can pick up nuanced information from audio signals and we do it all the time, for navigation, communication and pleasure.

By means of good, generative sound design, it would technically be relatively trivial to use software synthesis to produce rich ringtone (and other signal) audio on the fly, which could convey meaningful information to a recipient.

I'm wondering why we don't see this more often?

Compared to visual signs, the way sounds are being used for symbolic communication seems somewhat primitive.

An average app/system has a shallow set of static sounds which lets you at best discern a handful of event types.

Sure, static rendered audio files are easier to distribute across platforms and are less taxing on the device resources. But modern devices have more than enough processing power for some intermittent near-realtime audio processing.

And of course, extracting information from sounds can fail in noisy environments, but visual fallbacks can help and it would be the job of a sound designer/programmer to produce resilient tones.

However, I believe that generative, contextual ringtones could be quite useful in a lot of ways.

Can you point out good examples of where such on-the-fly sounds are being used?

Why isn't this more mainstream?