If you set your parking brake properly, this does not happen.It also needs "parked downhill assist" because it is so clunky when you put it in reverse while the car is facing downhill, it needs an elephant to push it and the transmission clunks and chunks so badly it feels like it's falling out.
What I have been doing to prevent this from occurring is, before putting the car in park, apply the parking brake all the way (when on a slope you have to engage it more) then slip it into park. no more abrupt shift from park.
It is normally for any car to have a hard disengage from Park when on a slope, as you are essentially resting 3000ish lbs on a tiny parking pin That is why cars have a parking brake.