Interesting post. For me, when I purchased my original iPhone I bought the minimum. When I bought the 6s I bought the 64gb. Then I started getting into a GoPro and found myself creating videos and taking way more pictures then I thought. I also found myself in need of more apps. Now my storage is getting tight. So I ordered the 128gb iPhone 7 plus this time around.
I have a friend who ordered the iPhone 6s Plus 16gb and once she runs out of space it becomes a headache not to mention a constant choice between what pictures and apps to keep. Also as a result she has lost texts, pictures and notes. Now she can't wait to get her new phone. She wound up ordering the 256gb and doesn't want to worry anymore about running out if space.