Please note at the processors under the study -
Ampere processor has 128 cores ($5.8K or $45 per core), AMD processor has 64 cores ($7.9K or $123 per core), Intel processor has 40 cores ($8.1K or $202 per core),
Still Ampere's cost is 50% less than AMD/Intel's cost 'in per core' price. So, I think, article used correct word 'fraction'.
Yes, there may other advantages in Intel/AMD, which I do not have knowledge of the below ex: - clk speed, - L1/L2/L3 cache size and speed, - peripherals ... - etc (I tend to feel, Ampere is better in these too. Question is about chipset, SW base etc )