By Zaheer Kachwala (Reuters) -T-Mobile said on Monday insider Srinivasan Gopalan would take over as CEO from Mike Sievert on November 1, marking a leadership transition as the telecom company works to defend its 5G lead in a saturated U.S. wireless market. Wireless carriers have been grappling with slowing subscriber growth, rising competition and increasingly cautious consumers unwilling to pay for premium plans. The industry has also witnessed significant consolidation in recent years, exemplified by ...