Maths
Clearly maths is not the authors strong suit. Or they lack basic understanding of the oculus platform.
Or they are deliberately misleading us for the sake of a headline. Either way it's poorly researched.
Oculus rift comes with headphones, and a camera, and a wireless xbox controller for $599
Oculus touch comes two controllers and a camera for $199
Oculus Total = $798
The earbuds and additional cameras are optional extras. Reality check VR has already shown that 2 cameras are enough for room-scale, so additional cameras aren't really a necessary purchase. The headphones that come attached to the rift are really good actually, and aside from them getting caught in my hair, when I take the headset off, they are fine.
HTC vive, comes with no headphones. and two controllers and two base stations
Total = $799
Your own headphones = $Whatever you want to spend.
So Oculus is cheaper by a dollar than the vive, and has free headphones and a free Xbox controller? And has a lower price entry point of $599 for those that are happy playing cockpit based and platform vr games and don't want the touch controllers.
Both Vive and Oculus require gaming pc. The one for oculus would be about $500 dollars, the one for Vive about $600 dollars, (because the oculus has asynchronous timewarp and requires a lower spec PC now.)
Just for giggles lets look at PSVR:
PS4 Pro = $399 (I personally don't think the base PS4 will cut it)
PSVR = $399
2 x PS move controllers pack = $100
PS4 camera = $60
Total = $958
So that's quite expensive too, but you don't need the pc. PSVR is expected to be a less "premium experience" but we'll have to wait and see.