Single threaded performance and overall performance are quite different. But I'm not sure that Oxford is the most authoritative source here, as they are talking about a "computer" which is an awfully vague term. Wikipedia uses transistor count of an IC, which is much more specific:

https://en.m.wikipedia.org/wiki/Moore's_law

Would be interested to know if the process inside Oxford's is as precise to distinguish, or if they intentionally dumbed it down.