Solid state drives tend to respond well to parallel reads, so it's not so clear. If you're reading one at a time, sequential access is going to be better though.

But for a mechanical drive, you'll get much better throughput on sequential reads than random reads, even with command queuing. I think earlier discussion showed it wasn't very effective in this case and taking 6x the space for a marginal benefit for the small % of users with mechanical drives isn't worth while...

Every storage medium, including ram, benefits from sequential access. But it doesn't have to be super long sequential access, the seek time, or block open time just needs to be short relative to the next block read.