People need to calm down and stop being so defensive. He isn't calling your iMac and MacBooks "bad computers", he simply means they aren't good enough in the pixel pushing department for the rift; and for what the rift is, he is 100% right, there just isn't a mac out there that can do it.
Reading these comments, there are a lot of people who don't understand what the Rift/Vive is vs other VR HMDs. The Rift is the high end/Mac Pro of VR HMDs targeted at a very narrow set of users. VR has had some false starts, mostly because they made cheaper under-powered and ultimately compromised products to try hit larger numbers of users, and they have been crap because of it. You have to make the case for VR before you make the case for mass adoption of VR. Mass adoption will come later.
Also, there is already a VR market that is aimed at low cost of entry and mass adoption. 360 degree video-type experiences are available with things like Google Cardboard.
Apple, Google, Facebook, Microsoft, Sony, nVidia, AMD, Samsung, HTC, and others are putting big money into VR. It's coming, and it's going to be big. If you know anyone who has a "good computer" and a Rift or Vive on preorder, give them a visit once they get set up. You need to try it to understand how big this is going to be.