https://www.cnet.com/news/senate-democrats-want-another-hearing-on-t-mobile-sprint-merger/

"The merger of T-Mobile and Sprint would reduce the number of national wireless carriers from four to three," the senators said. "This reduction in competition raises a number of important questions that the committee should address."

Opponents of the merger say the reduction in competitors would consolidate the market too much. Supporters, however, including the companies, say scale is needed to build new 5G infrastructure and to compete in a market that's quickly becoming commodity.