Yes, that’s probably the historical background. Intel never had much incentive to pursue ultra-low power, while for Apple this was the central design goal from the start. And the practical consequence of this is that Intel is stuck in a thermal corner (which is also the main reason why it has to go horizontal) and Apple has much more scalable tech. Their P-cores offer performance close to that of Intel P-cores at much lower performance, and their E-cores consume almost no power at all.
And I think it’s entirely incorrect to say that Apples E-cores have no place on desktop. Quite on contrary. They can take care of low-priority background tasks, minimizing context switches and cache trashing on the main cores and freeing them up to do more performance-sensitive work.
It is entirely possible that Apple will eventually develop the E-cores more into throughput support processors (there were major performance improvements post A14 in this domain), but the focus in energy efficiency and background work execution is unlikely to change. This is also evident from Apples balanced core configurations which are optimized for real world usage and concerns rather than more artificial metrics.
No, they wouldn’t be useless (for the reasons I explain above). But Apple doesn’t need a specially designed core to maximize server throughput. Their P-cores are both faster and use less power than Intels E-cores.
And if Intels’s P-core scaled well in respect to power usage they wouldn’t need the E-core for throughput either. AMD doesn’t.
