I still struggle to see the point these days -- swapping CPUs and RAM makes little sense even on Windows; RAM sizes have remained stagnant for years and the small generational speed increases on CPUs mean you'll likely need a new motherboard anyway by the time the cost/benefit is there. Disk is a non-issue as there are external enclosures that aren't expensive, and performance over Thunderbolt is as good as PCIe (because it is PCIe).
Performance-wise a MacBook Pro is and has been a great machine and not incredibly expensive, plus you get the portability aspect. For the "semi-professional" market that a Hackintosh is appealing to, most folks would be better off with a MacBook Pro and a Thunderbolt dock. You also miss out on a number of core features of the OS because the hardware that supports them doesn't exist.
Combined with the headache of keeping the machine current, it's not really a good tradeoff for a couple hundred bucks. You'd be better off buying a used MacBook Pro.
Try a couple of thousand dollars. My build is 1K cheaper than a similarly specced Mini without an eGPU. A comparable Mac Pro (yes, Xeons and ECC) is 7.2K USD.
I was thinking more about what happens when parts fail, especially if you're nowhere near an Apple retailer. I used to be able to swap out disks and RAM with my MacBook Pro. Not any more.
