Do you still appreciate the police warnings knowing you only get them because a group of people saw one and started fiddling with their phones, probably while driving, to let the app know?
Should be doable with an auto-hot key type of script.
More likely possible on android.
Just as easy on iOS. You can have an NFC button associated with a Shortcut, so as long as Waze exposes "send accident report at current location" to Shortcuts, it would be very simple.