Industry has gone to shit with trends. The reason they don't equip cellphones with an external antenna is because they (phone makers) consider the phone's looks (sleek-ness) to be more important than reception; bright OLED QHD autostereoscopic 3D touch screen more important than battery life; built-in camera(s), 3-axis accelerometer, and GPS more important than lowering cost or improving build quality; etc.
I think the popularization of Li-Ion batteries is what really changed things. back in the day, portable (aka battery powered) devices used to have ONE function and they were designed to be best at that one function. They lasted dozens, if not hundreds, of hours on two AA's; were built rugged at the expense of cost and size, because portable devices are likely to be dropped or taken out in the rain etc; and were kept as simple as possible. Today, designers SAY they take battery life seriously, but when their designers say the device will last two - three hours on a fresh charge, the business leads say: okay, good enough; they can just charge them when they get home anyways, who cares.
I guess nobody has the balls to produce a phone that has just an old style monochrome display, because it's good enough and is easier on batteries. They fear that they won't compete with Apple and Samsung and Google etc and so they just follow the trend and produce yet another product that has nothing different about it from all the other products out there.