Doesn't really make a difference with MorphOS' old TCP/IP stack and ancient SANA-II interface, especially for Internet download/upload speed. Or how much faster is that on the X5000 using similar (same?) NIC than on the Mac mini?
> NVME, USB 3.0
MorphOS drivers?
> and two PCIe x1 expansion slots.
Yes, but at the expense of the special form factor of the Mac mini.