Overall this bell seems like the wrong solution, and it took me a while to realize not every country has outlawed headphone wearing for bicyclists, something I guess I took for granted.
It doesn't make sense for a car driven to use headphones, so not sure why it'd make sense for other vehicle-users to use them either, as you say, we really do use our ears to help navigate traffic so allowing people to be so careless seems... Careless?
You can turn up your car stereo and mow over pedestrians undisturbed in your two ton death machine yet I'm not allowed to cycle on a bicycle-only path with with a podcast and transparency mode enabled? For my own safety? Safety from car drivers that fell asleep driving with their stereo on?