I work in the sector and can definitely see some investment value. I don't like fixed line operators but I can see good times ahead for large carriers. Remember when oil was only $25 a barrel? Barely worth sucking it out of the ground and definitely not worth putting much money into exploration. So oil companies sat on their hands, demand for oil caught and indeed exceeded supply and the price boomed.
It may be several years away but I can foresee similar issues for bandwidth. After the dotcom fiasco, carriers realised they had installed far more fibre than was necessary - there was a fibre glut. Since then, very little investment has been put into extending existing bandwidth capacity but demand is still growing. As more and more video is transmitted over the Internet, we may end up with the actual demand people were dreaming about in the heady days before the dotcom collapse.
Anyway, as whathome says, unloved and undervalued sectors are gold for the longterm "buy and hold" investor.