how did it come to pass that the more concentrated a sector the better? the exact opposite is true. excessive concentration means an oligopolistic or oligopso

how did it come to pass that the more concentrated a sector the better? the exact opposite is true. excessive concentration means an oligopolistic or oligopsonistic sector that is holding everybody hostage: clients, employees and the political / regulatory system at large adulation of "bigness", if not with ulterior motives, is naive