As density increases so does the spare area. In the Enterprise space 1DWPD SSDs are classified as "read intensive." Even a 1.92TB "read intensive" drive has a write endurance of 3.5PB. Whereas an Enterprise grade 3.5" HDD has a write endurance of 550TB/year for 5 years. That comes out to 2.75PB of endurance. Increasing size only increases write endurance. Get to a 12.8TB "mixed-use" drive, or 3DWPD, and you have 70PB write endurance which is vastly more than a 3.5" HDD.As density increases, durability goes down. Not sure how much farther they can push it if they want Enterprise drives to last more than a few years.