The harddrive is the bottleneck in a pc, no matter how fast and how much ram, permanent data still has to be read/written from/to much slower harddrives.
My first PC magnetic permanent storage was a tape cassette. That was not fast but then my programs were not huge. There was no data to speak of. The CPU in this article is so far beyond the Z80, which was pretty speedy, that the PC would be in the workstation category. I don't know if workstations are at all popular anymore, but the old workstations we had would be left at the gate by any off the shelf PC now. I am still waiting for the UN to put all of history into their database, but they have a significant bottleneck in that person who keeps insisting that they have no history at all but historical fallacies. We probably would not need more than a dozen general purpose digital computers in the world even now if we took a serious look at what we are trying to do.