Would be cool to buzz the message itself in morse code, though todays buzzers are so weak I don't think I'd be able to make it out (if I knew morse code, that is).

But would be cool with a separate buzzer of sorts where you get the normal buzzer notification and then hold a finger somewhere specific and get details that way.

Pretty clever! Not a bad way to passively learn Morse code too.

iOS supports having notification sounds synchronized with the haptics; I wonder if generating the text tones as audio files and assigning those would have been an easier approach.

Just have to use the share sheet on an audio file and choose "Use as ringtone". Shortcuts/Automator might even be able to make this automagic.

We’ve come full circle: the iconic Nokia default SMS ringtone is S-M-S in morse code, and the “Ascending” ringtone spells CONNECTING PEOPLE

Many many many years ago, I wrote an android app that allowed you to set the ringtone of the device you were ringing for that call (yes they had to have the app installed etc etc, and had given you permission to do it). I did release it but the market problem I had was that iPhone's ringtones were not something a client app could change, let alone in the background and even less so without direct permission of the user.

So anyway, if you want to do something like that, it's back to android I'm afraid. Don't worry, there's no patent and there's prior art (i.e. my usage). FWIW - the closest patent to it was made by a TV manufacturer that would allow you to find the remote control by playing a noise etc directed by the TV !