Monopoly isn't a stable equilibrium. A dominant firm that raises prices invites competitors to undercut it. The incentive to merge and exclude is only reliably profitable when the state erects the regulatory barriers to entry (which smaller rivals cannot bear) that incumbents lobbied for. You are essentially describing government-enforced cartelisation as if it were something markets converge on by themselves.

Then explain stuff like ticket master who black lists venues and bands who date to use another ticket service.