The idea is that the islands offer sustainable living, without the need for privately owned cars.

The Malaysian State has partnered with local developers to create three new islands Penang, Malaysia to serve as cultural, business, and residential hubs. The islands will house about 15 000 people in a very sustainable and eco-friendly way. One of the biggest factors of the islands is that they will be free of privately-owned cars. Transportation on the island will consist of autonomous boats, vehicles, and air travel, leaving the 4,500 planned acres car-free and pedestrian friendly.

https://www.businessinsider.co.za/biodivercity-islands-coast-of-malaysia-connected-using-autonomous-travel-2020-8