Because they only show you what a camera CAN do, and conveniently forget what it can't.
Same goes for "evangelists" of any platform.
Really, what makes a tool great is it's ability to remove limitations and expand possibilities. No camera or light or anything is going to give you a one button way of making great images, but the best get completely out of your way.
DSLRs were the opposite of this. No I don't want to shoot narrow depth of field shots without lights at night. I want to do a hundred other things, and most of these other things don't work well at all on a DSLR. If you think about it, footage form just about any other platform looks more varied than DSLR stuff. Even an Ex1, with its 1/2 inch chip, allowed you to shoot a much wider range of things in a much wider range of situations. If you added a 35mm adapter you were golden. With DSLRs, once you've seen one rack focus across a wedding veil (oops, moire...), you've seen them all. DSLRs limit your creativity to F 1.2 - thats' not empowering, that's narrowing your approach to a hackneyed cliche. I mean, the damned things wouldn't let you shoot bricks - have you ever been to Montreal? it meant not shooting on the street at all, ever, unless you were shooting what I have come to call "the wedding video look"- a close-up floating in a sea of blur - again, all these shots look the same - it's all very narrow and repetitive.
Epic (and I would imagine to quite some degree Scarlet) raise the ceiling of possibility so high you almost never hit it.
Can I shoot detailed scenes at f8? Yes. Can I shoot narrow depth of field if I want to? Yes. Can I shoot in low light? Yes. Can I shoot very high dynamic range scenes? Yes. Can I shoot slo-mo? Yes. Can I pull stills for print? Yes. Can I use jarred camera movement without problematic jello? Yes. Can I mix colour temps in post? Yes. No problem. Can I lug it through a run and gun situation? Can my wife fly it on her Steadicam for prolonged periods? Yes. It weighs almost nothing.
Epic is the camera that never says no to you.
Recently, I discovered a new reason to love 5K, even though, with all due respect to Jim, the probability that our work, which has a very short shelf life, would ever need to be 4K, for at at least another 2 years, maybe more, is exactly 0% .
I am working on a project that requires tracking tiny objects within the frame for compositing. If it were shot at 1080p, even 2K, there would be no way the tracker would have enough pixels to be able to follow these objects well. With Epic? Once again, the camera is saying yes to me, not "No and why don't you just shoot more rack focus and slider shots at f1.2, it's what all the kids are doing".
Also, let me tell you, greenscreen at 5K is a thing of beauty. You didn't see any greenscreen in those "famous" 5D videos like Reverie. There's a good reason for that.
The above is also why I do not trust Zacuto's Why You Should Continue to Buy Expensive DSLR Kits From Us Camera Shoot-Out. It's a test of how a DSLR can be adequate, and shows you next to nothing of when it breaks down, shows you nothing of situations when only two cameras - F65 and any Red model, would actually still say yes to you. (Not to mention it's a test that doesn't really understand RAw workflow at all - but I digress.)
Our Epic does not do the hard work of cinematography for us, does not do the casting, location search, production management, styling, visual research, nor lighting. But I love it for another thing it DOESN'T do. Say "No" to me.