It also inadvertently proves their point. The strength of Apple hardware is the OS integration. This level of integration and polish is only possible because of the limited components they have to support. Even if you have powerful components on the PC side (Windows or Linux), you're at the mercy of a few different vendors and how well they support the hardware. And even if you get supported components, it's possible to get yourself into situations where your configuration is sub-optimal.

Versus a Mac where you can just start it and get working. It's possible with PC hardware, but it takes more work for the customer (or vendor).