Not entirely true. Ask anybody who used a computer in the late 80s, early 90s, and Apple was way ahead. SCSI on the desktop? Check. A completely USB connected home computer? Check. In fact, it was likely that Apple's early insistence on cutting edge tech is at least part of the reason nobody bought them until Steve Jobs came back. SCSI on the desktop? Who the fuck can afford SCSI on the desktop, and why the hell would I need it?
I agree however that with core components (processor, graphics card, etc.) Apple's computers are consistently behind PCs. BUT...Apple isn't really interested in selling computers that run Crysis at 2560x5760 in full 3D, because they learned the hard way that such things only serve a niche market. They build PCs like Black & Decker builds coffee makers. You turn it on, it works.
Which is exactly why I'll never own an Apple computer. I don't give a shit about user-friendly or stability. I want to play with the naughty bits.
I do think in certain areas they are ahead. I hate Apple to the core, but I can't even argue with the quality of the Apple displays. The original iPod scroll wheel was way ahead of its competition, and maybe touchscreen smartphones were inevitable, but the iPhone made it work before anyone else did.