It's easy to forget that when mobile cellphones first appeared, they were far from the miniature computers we carry today. No high quality camera, mp3 player or Internet access here!
For the lucky few who could afford one, the mobile cellphone required either special holsters, or just to be carried around in one hand or in a briefcase. What's more, it was certainly not taken as read that everyone you wanted to call would also have a mobile telephone, and even if they did, the signal coverage was so bad that you had little chance of being able to even hear them.
Somehow, though, phones became a status symbol, and with technology moving at light speed, it was only a few years before the size of phones decreased and their capabilities increased.
If you'd like to evoke the style and feel of the 1980s, this is a great design to choose.