Consider the Laptop for a second.

From a cheap chromebook up to a Macbook Pro they all share the same design DNA. This form: screen on top, keyboard and trackpad below, ports on the sides hasn't changed since the mid-1990's. Thye've gotten thinner and faster but the chassis layout remains the same.

Now think of how many articles you have read in the last decade that complained that laptop design innovation had stalled. Its likely zero.

My point is that smartphones quickly reached their natural form factor and have stayed that way. All those 'innovative' designs we had previously were lots (and lots) of attempts to find the natural endpoint. Apple just got there first and nailed it with the iPhone 4.

Many products have reached this point over the centuries. Ever wished there was more innovation in the designs of nails, house bricks, paragon umbrellas or cameras?