Because it's NOT A PHONE. yes, it has a phone app to make calls but that is one of the least used things of the SMART DEVICE.
It's a portable computer with all of the human knowledge in the palm of your hand. And it's all wireless.
This isn't the flip phones of yesteryear anymore. This is the future now.
It is still a phone, thats why its called iPHONE and not something else and while I agree with you that the functions have been greatly enhanced and made better. The actual use case still remains the same.
In the past these devices were called PDA, Palm and touch-screen phones and similar devices already exist for more then 10-15 years. All these devices had one major requirement they should be ultra-portable and fit in your pocket/handbag in the first place.
The same is/was also true for some of the devices that smartphones are replacing, like point-and-shoot cameras. Most of the cameras were small enough that they could fit in your pocket or small handbag, but since the camera sensor of smartphones is up to par with those cameras, there is no more need for point-and-shoot cameras, but a smartphone will not replace a professional DSLR camera, because they have a different use cases.
Next example, the mp3 player, the ipod will be replaced by the iphone, because the use-case is very similar... Its an ultra-portable music/media device that should fit in your pocket!
Think of the little flash light some people had on their keychains, that is replaced by the led of your phone.
Apple just introduced Apple Pay with the ambitious plan to get rid of your wallet and use your iphone for future payments. A lot of people have their wallet in their pockets or handbags.
Tim Cook even brought up something like, we want to want to clean up your pockets with one device. The next step will be that your iphone will replace your keys. With cars this is already technically possible and we are already seeing "smart" locks on the market.
In the end your phone will become the universal pocket device that will replace most of the stuff that we used to carry with us all the time and therefor the use-case and basic requirements remain very similar to what the mobile phone had 10-15 years ago...
When it comes to the phone function, the only thing that has massively changed in the past 5 years is how we communicate with each other. In the past we only used phones (voice), but now we also communicate via texting, social-media, facetime, skype etc.. But in the end we want to be able to have this device always with us and a huge part of the users still want to carry it in their pocket and Apple knows this! And the device is made to fit in your pocket, so it should also survive the normal day activity in a pocket without bending, my previous devices did never bend/brake before either.
And if the world has changed so much and bigger is better why is not everyone using the cellular ipad and ditch their smaller smartphones and phablets, since we are not using our pockets anyway??
By the way, when I bring up handbags I mean that women mostly use handbags and most men use pockets.
Seriously man!? Did you actually read this study in full? This study was CONCLUDED in 2007. Started in 2003. You really don't thing a few things have changed since then?
As of January 2007, the study has conducted street interviews with 1549 participants from eleven cities in nine countries on four continents. Data collection started in 2003 with Helsinki, New York (NYC) followed by Milan in 2004. Beijing, Jilin, Hyderabad, Tokyo, Los Angeles (LA) and Seoul were done in 2005. Delhi, Kampala, and Tehran were done in 2006. The research team collected at least 50 male and 50 female participants in each city with additional data collected dependent on the availability of local resources.
You are right about the date and I was aware about that, but in 2005-07 we already had fairly big touchscreen phones, but they still had a very similar use-case as smartphones today...
Since I don't find anything newer then this and I very much believe that not so much has changed in the use-case of these ultra portable devices in the past years we can still use these numbers.
If you have newer numbers/research I'm happy to look at them...