His point is that a Microwave adds convenience at the expense of ability. In that a Microwave doesn't cook things as well as an Oven does but it cooks them faster.

In that same way an iPad adds convenience at the expense of ability. You can carry an iPad places you don't want to carry a desktop or laptop but it can't do as much as those devices.

Though all of this is beside the point because your original comment treated the statement "no one needs" as if he were saying "there's no value in" when in fact that wasn't what he was saying at all.