Teklock
Although what your saying may seem like it makes sense actually you are quite wrong
Adding this would actually be quite easy for the development team
Yes every car is different and yes every canbus is different BUT the messages in the canbus get translated to something different that the Dudu device can understand, in the actual software inside the Dudu/the physical display of parking sensors for example is handled in exactly the same way no matter the car so this could be implemented on the software side pretty easily. It could be added so that all vehicles can have sound.
Dudu developers could easily add an option for reverse sound beeper and have different tones and volume levels etc if they wanted to but it all comes down to if they want to invest the time on developing this or not...