The $116 billion business of selling cell phone calls in the U.S. faces a long, ugly decline. That petrifies just about everyone in the industry except Roger Linquist.With his gray hair and grandfatherly demeanor, Roger Linquist hardly seems like the kind of guy to kneecap a $116 billion industry. Yet the 71- year-old chief executive of MetroPCS cheerfully and brazenly promises to do just that. He aims to bring down the lucrative business of selling cellular phone calls, a business that for four decades has grown bigger and richer with every passing year. MetroPCS, which Linquist founded 15 years ago,...