Apparently over 80% of the world doesn't agree with the OP. Why could it be? Apparently they only care about what they can do with the phone they have in their hand, not a bunch of models listed in a table showing some argument, such as being stuck at an earlier major version. And some random bits:
* on iPhones they can't install CyanogenMod, Ubuntu Mobile, a custom ROM, newer experimental OSs. versions, Firefox.
* on iOS they can't find enough free apps, they end up paying 5 times more. It's a money trap.
* On iPhones they can't install Android KitKat neither since iPhones are stuck on iOS.
* Newer iPhones are stuck at similar specs to the previous versions mainly they couldn't easily keep the API consistent if they had launched a 6.0inch iPhone and a 2inch one.
* They can't install iOS on a phone with very large screen, with dual sim card, a very small screen, a phablet, a water proof phone, a watch, a virtual machine, a game pad
* iPhones are mostly oversold in US, due to carrier subsidy model. Most people end up paying higher sums during the whole contract, beyond the initial money they paid. It's a money trap to suck more from customers.