To be fair, this more or less just brings their policy closer to the per-core license models of lots of other enterprise software(Such as Windows Server), which is no less draconian or arbitrary, but seemingly more profitable with the popularity of the per-core licensing model.
I think it's safe to say the driving force here is VMwares desire to increase their bottom lines by removing a "loophole" in their pricing model, with no external forces required to motivate that change. The AMD processors will still be cheaper per core than the Intel ones to use and operate too so it doesn't flip any competitive advantage.