The bandwidth of these drives are increasing due to the fact that the rotational speeds are tending to remain the same while the density is increasing. So, as t

The bandwidth of these drives are increasing due to the fact that the rotational speeds are tending to remain the same while the density is increasing. So, as the linear in track BPI increases so does the throughput. Tracks per inch, which is where most of the density has been doesn't improve bandwidth. This is where a lot of the density improvements a few years ago was coming from (higher TPI). At one point the TPI was actually higher than the linear BPI, which was something completely non-obvious to me when I discovered it. HAMR is an increase in linear BPI, so expect these drives to get faster.