The Sprint/T-Mobile merger that was proposed a decade ago was denied by the FTC. The recent merger was allowed by the FTC, thus reducing our number of cellular companies.

If you mean “the real system first described as ‘capitalism’”, no, it doesn’t.

If you mean “the abstract, never realized ‘ideal’ system that defenders of capitalism appeal to whenever criticism is levelled at real-world capitalism”, that's harder to assess since the descriptions of that system tend to be both internally inconsistent and incomplete. But nothing usually hear in those encourages competition, usually it's defenders just assert as an article of faith that restriction of competition requires active cooperation of government.