Ahh, that delectable scent of hyperbole... As expected from a site called "Apple Insider" of course.
Probably they are upset that the Note 4 got the
"Best performing Smartphone display that we have ever tested" grade from DisplayMate and that the + Plus then couldn't de-throne it. AI builds their whole article on the higher resolution of the Note 4 display being a waste of resources, to which DisplayMate clearly disagrees.
If the Note 4 turns out to perform well enough despite Samsung's prioritising of the screen quality before CPU performance, then perhaps it is actually Apple who have wasted resources on CPU power that isn't harnessed in day to day use anyway? And so far noone who has actually tested the Note 4 seems to have complained about it being slow in any way. All we've heard from real-world testing is that the screen is stunning. If this supposed "extremely poor performance in high definition" would actually be true, I think people would have noticed it already.
At any rate, we won't know what's what until the real, all-round testing of the Note 4 has been done. Or better yet until we the consumers who will actually buy the device have tested it for ourselves. Until then, this is all theory, PR, and trying to smear the competition.
And of course ultimately it comes down to which OS one prefers, and which device is best adapted to the large screen format in terms of functionality. Both the 6 Plus and Note 4 have stunning displays and I'm sure both will be able to handle any tasks we're able to throw at them just fine in terms of processing power.