"Absent large barriers to entry like economies of scale, network effects, or legal/regulatory hurdles"
Key supposition there. Because of the economic profits enabled by monopoly, corporations and individuals will disproportionately attempt to lodge themselves into niches where there are economies of scale, network effects, and legal/regulatory hurdles. Or lobby to legislate them, or create products that generate network effects and economies of scale.
Of course, not all markets are susceptible to any of those threats. But as a result they're open to competition, which quickly eliminates economic profit and makes companies occupying those niches much poorer and much less powerful.
Key supposition there. Because of the economic profits enabled by monopoly, corporations and individuals will disproportionately attempt to lodge themselves into niches where there are economies of scale, network effects, and legal/regulatory hurdles. Or lobby to legislate them, or create products that generate network effects and economies of scale.
Of course, not all markets are susceptible to any of those threats. But as a result they're open to competition, which quickly eliminates economic profit and makes companies occupying those niches much poorer and much less powerful.