Take numbers with a grain of salt, e.g., this link says a 7200RPM 160GB SATA drive from 2004 is $107, or about $0.67/GB, instead of the $5 claimed in post.
I know for a fact that in 1999 (25 years ago) when I was running an ISP that Seagate Barracuda 4GB SCSI-2 Ultra Wide drives for example were costing $300/drive rounded; I used to buy hundreds of them. I have an old purchase order framed showing such and those were very much a premium drive back then.