I dont use my phone as my primary computing device, but I still like larger screens. My 6.7"-display phone fits nicely into my pocket, the large screen works well as my bike computer display and I like reading books with it and it also has space for more battery capacity.
The 12 & 13 mini with their 5.4 inch screens are huge. The SE 2nd & 3rd generation at 4.7 is already too big. The 1st SE's 4 incher was probably a little too small, but a slightly bigger form factor combined with thinner bezels would probably allow for a screen of about 4.2-4.5 which should be perfect.
In fact an increasing number of people seem to want 2 large screens in their phone.