Competing workstations of a similar size support more memory, disks and PCIe slots. (And, of course, they have newer CPUs than the Apple Pro.) Competing workstations of a much smaller size match the Apple Pro for for memory, disks and PCIe slots.
When did I say anything about the internals? I was only ever talking about the case. The current internals are a joke. The current generation Mac Pro is a disgrace to the original which was the fastest windows workstation you could buy for a grand less than the closest Dell.