It's a portable computer. The "phone" in smartphone is an anachronism of a bygone era, and actually seeing people using one as a phone is rare now.
People browse. View media. Post pictures. Read Facebook posts. They do things where the attributes that make a small smartphone good for one handed use conspire against usability with two hands (browsing Reddit on a 4" screen iPhone, for instance, is an exercise in precision. Many downvotes were accidentally dished out on HN courtesy of small screens). If 95% of your use is as a landscape portable computer, that 5% use of "one handed through a parking lot" should rightly suffer.
Of course some people really do prefer smaller devices, and those options need to stay around (the Nexus 5, for instance, is still a premiere Nexus device). But a lot of people really do like "phablets".