Holy beaver these arguments are quite literally the silliest thing of all time.
The only thing that defines a console as "next-gen," is whether or not it is the "next generation" of console hardware for that particular company. For example, the Wii is still 7th gen, regardless of how much less powerful it is than the 360, simply because it was the next iteration of Nintendo's hardware. The Wii U is the next installment of Nintendo's hardware after the Wii, so therefore it is the next generation.
That's all that next-gen means. If you want to argue that it's not in the same category as the PS4 and X-Box One in terms of power, go right ahead. But that's a completely different argument. Saying that something doesn't qualify as 8th gen simply because you don't think it matches up well with other competitors is like saying the iPhone 5 doesn't really count as the next generation of iPhone because it doesn't match up well with something that comes from Samsung.
At any rate, I think it's rather hard to claim that you have "nothing but respect" for a company, and then dismiss their console as a failure a mere six months after it launched. Plenty of gaming systems have turned things around after poor starts (most recently and notably being the 3DS, another Nintendo platform coincidentally) so let's hold off on the cries of failure until we're a little deeper into this next cycle of consoles.