Unregulated markets tending to monopolies means that markets require regulation, not that a monopoly is a market.
Unregulated markets are not the "natural" state of a market, and not the meaning of a "free" market. A free market is one in which there is competition and new agents are able to enter the market, not ones where there is no law.
Unregulated markets are not the "natural" state of a market, and not the meaning of a "free" market. A free market is one in which there is competition and new agents are able to enter the market, not ones where there is no law.