I've always explained to my friends and family that the only real requirement of one passing a PhD is stubborness (or tenacity if I'm feeling charitable). It's certainly not intelligence that's the determining factor, although there is a minimum threshold you need to be over. You have to be stubborn enough that despite all the crap the Economist article is describing, you still want that certificate.

But there is real value in doing a PhD at a prestigious university: it opens doors. Many many doors. I think of it as a cognitive short cut for others that, magically, you're now someone worth listening to. I actually don't like this, but that's what I've observed on multiple occasions.