As much as I hate to admit it but the buttons vs no buttons argument feels like Blackberry vs Smart phones.
You had and still have people that love a keyboard on a Blackberry but most have moved on to touch screens. The Blackberry people are considered old fashioned and behind the times.
You have kids growing up now exclusively using phones, tablets and touch screens. Buttons aren't apart of their world.
I fear buttons on controllers may be the new Blackberry. If the NX has it where you can map and kind of button combination you desire along with haptic/tactical feedback, it could be a game changer and the most forward thinking Nintendo has done in years.
It made sense to drop physical buttons on phones because those need to be as slim as possible, and writing text is only one of the things you do on a phone, and even when you're touch typing, making a typo isn't a big deal.
When I'm playing a game, missing even 1% of button presses is the easiest way to make me stop playing. I also don't need to put a controller or even a handheld in my pocket, I got a backpack for that.
A gaming device is also specialized hardware, whereas a smartphone is a versatile product that does a wide range of things. Putting physical game controls makes sense on a gaming device because it's meant to play games.
My point is, comparing this to phones is a shitty analogy. I've seen it many times in this thread and I'm honestly shocked to see this mentioned so often.
Not to say that haptic input could never work, but "because phones!" is a nonsense argument. Different devices with different use cases.