This is definitely not true. I worked in the smartphone industry before and at the time Apple started making large phones. Rumor had it Apple stuck with small phones because Steve Jobs wanted them to stick with the same screen size to avoid apps looking different on different iphones. Regardless, everyone was making them large because it provided the best user experience and eventually Apple switched to it as well because it put them at a disadvantage in terms of user experience. Even the term 'phablet' was coined before Apple switched to large phones.