I think it'll be a while (if ever) before the Mac Pro moves to an ARM CPU. It's not that I think Apple can't build a CPU to compete in that space, it's that I

I think it'll be a while (if ever) before the Mac Pro moves to an ARM CPU. It's not that I think Apple can't build a CPU to compete in that space, it's that I don't know that there's a large enough market to justify building that CPU. ECC memory, lots and lots of PCIe lanes, dual CPU capable, etc. etc. You can take the iPhone CPU and make it into an ARM CPU for a laptop that can compete with Intel and AMD (somewhat) easily. That same architecture is in no way reflective of what people expect out of a workstation. Unless Apple is going to start running all of their own internal workloads ("Apple Cloud") on their own CPUs, I don't see it happening. And in order to do that, they're going to have to get mainline OS support for it, which again is a very different path to market than doing everything in-house with OSX.