It’s a fkn automatic transmission; hill start assist is utterly useless unless you have one leg. If it was a manual transmission I could see this being useful, but not in an automatic transmission. The reason being a manual transmission requires skill to manipulate three pedals with two feet in tandem. You must press in the clutch with your left foot, take your right foot off the brake, and move your right foot to the gas. In the time you move your foot off the brake to the gas you must also release the clutch to get the car moving. With your foot off the brake and the clutch disengaged, the car will roll back. Thus a hill-assist mechanism is useful for one inexperienced with a manual transmission*.
For an automatic, there are two pedals: a brake and gas. The number of pedals matches the number of legs a normal person has. If this person has half a brain, then this person doesn’t need hill start assist. You come to a complete stop at the top of the hill and apply the brakes with right foot. Then use left foot to hold the brake pedal while stopped and waiting. When it is time to go, apply gas slightly with right foot and gently release left foot off the brake pedal. Simple and effective. Like we need more electronic nannies in our cars for something as trivial as coming off a stop at the top of a hill. Learn to use a car people!
* There are ways to get around hill starts on a manual without hill-assist. One involves using the handbrake (if you’re not driving a car with foot-pedal parking brake): set the handbrake at the top of the hill and when it’s time to go slowly release the handbrake and manipulate the pedals like a normal start. The other method involves a trickier pedal manipulation where you slowly release the clutch to its friction point before releasing the brake and moving to the gas pedal.