Why do the largest oil tankers use the Lombok Strait instead of the Strait of Malacca?

The largest oil tankers utilize the Lombok Strait instead of the Strait of Malacca primarily due to depth limitations.

While the Strait of Malacca is a major shipping channel, its southern waters are relatively shallow, often reaching depths of only 90 to 120 feet (27 to 37 meters). Because the largest oil tankers have drafts that are too deep for these shallow passages, they cannot safely navigate the route through the Malacca and Singapore straits.13

In contrast, the Lombok Strait, located between the islands of Bali and Lombok, offers significantly greater depths, exceeding 3,600 feet (1,100 meters). This allows the world's largest vessels to transit between the Indian Ocean and East Asia without the risk of grounding.23