IMO it depends how long you are staying and the intent of your trip. We stayed for 5 days with no car and were fine.
BUT we had previously stayed in Waikiki and rented a car for one day to do Dole plantation, North Shore, Pearl Harbor, and drive around the island. (Yes, we did all that in one day and did not feel rushed, with 2 kids.) We then did a cruise with excursions on 3 other islands. Our last 5 days of a 2 week trip were intended to be relaxing sit around the pool/beach/spa days. We walked over to get basic groceries, ate at MonkeyPod once, and the rest of the time were content at the resort.
So if you are looking at Aulani as a relaxing resort/beach stay, I think its fine not to have a car. If you are considering it a home base to explore Oahu, you will need a car for at least a couple days.
BUT we had previously stayed in Waikiki and rented a car for one day to do Dole plantation, North Shore, Pearl Harbor, and drive around the island. (Yes, we did all that in one day and did not feel rushed, with 2 kids.) We then did a cruise with excursions on 3 other islands. Our last 5 days of a 2 week trip were intended to be relaxing sit around the pool/beach/spa days. We walked over to get basic groceries, ate at MonkeyPod once, and the rest of the time were content at the resort.
So if you are looking at Aulani as a relaxing resort/beach stay, I think its fine not to have a car. If you are considering it a home base to explore Oahu, you will need a car for at least a couple days.