I think 6s owners are angry about Apple. They payed much more and all they were given were 0.7inch more screen, a nano-second faster fingerprint sensor and the hoax technique 3D Touch, witch is basically nothing else than long hold software wise.
That's why they come up with "returned it, was too small"- as if they truly notice a difference. In daily life they don't notice their sandwich at a restaurant being 0.7inch taller or smaller, but hey, on a phone it's a burden...
If there was a cup holder on the 6s and not on the SE, they would choose that one to justify their purchase. A cup holder is as useful on a phone like 3D Touch, but hey, it's really worth a hundred dollars.
Did we really just compare 3D Touch on a phone to a cup holder in said phone? I mean I get it. You don't like 3D Touch. I'm not even going to get into why 3D touch dint just s long press (in all instances) because the point is moot since you've made it clear how pointless you find it, and that's fine.
But let's discuss the other differences between the 6s and the SE, because there more than you mention.
"Just .7 inches" is something like 20% more screen real estate. I could do the numbers or even find an online calculator but in typing this from bed. The take home point is it's not as small a leap as it sounds.
Expanding on that the actual image quality is better, has higher contract, better viewing angles, and is an overall better screen. It also has a higher resolution, though the same ppi.
The phone is thinner and with a larger battery, and so performance, including projected battery life is quite close to that of the SE (slightly lower battery life).
There is LTE advanced on board (perhaps useless today but those who are keeping the phone longer will reap benefits).
There is a barameter to track elevation,'something that fitness buffs may find useful (admittedly I run and don't find this useful in the slightest).
Perhaps there are other things I missed too, those just from the top of my head. I tried to list them in order of what I might dram important.
I say all of this as a family that literally has the entire spread of current gen iPhones. 6s plus. Two 6s. One SE. All of these phones are great within their own right. In inclined to agree that the SE gives the mist bang for its buck in terms of overall performance, but that screen size is a severe limitation for those that appreciate the larger screens. It's just as simple as that.
As to why people are getting angry and arguing about upgrade versus downgrade is still beyond me. Every one of us is likely to keep our respective phone for at least two years. This isn't something I've been able to say about an iPhone since the 4s. It's wonderful Apple has given their users choice amongs lt their smartphone line. Finally. Room to breath.