Loudness and Vibration

Why did Garmin with the Forerunner 970 connect the volume of the phone conversation with the volume of the notifications? At conversations you need the highest volume but with the notification alarms the lowest. Also that there is only one level of vibration doesn't fit to this pricey watch and a top model of Garmin. The Garmin Venu 3 costs less and doesn't have this problems.