The problem I see with 3D touch is, you have to remember, most people are on a 2+ year phone replacement cycle. So, it was introduced on the 6s/6+s, which is an off year (I'm going to guess most people are on the X years, not Xs years).
So those (like me) that went from 6/6+ to a 7/7+, 3D touch was already an old thing, that had already existed and become a part of daily life for year. When people like me got the 7/7+, no one talked about 3D touch, because it was already old news. I find myself forgetting to use it all the time.
So, it makes sense that many people do not even realize it is there. I still know a lot of people on 5s phones, that are just about to make the jump to a new phone, they will have NO idea that 3D touch exists unless someone tells them...
So those (like me) that went from 6/6+ to a 7/7+, 3D touch was already an old thing, that had already existed and become a part of daily life for year. When people like me got the 7/7+, no one talked about 3D touch, because it was already old news. I find myself forgetting to use it all the time.
So, it makes sense that many people do not even realize it is there. I still know a lot of people on 5s phones, that are just about to make the jump to a new phone, they will have NO idea that 3D touch exists unless someone tells them...