The problem is that governments forcefully prevent competition and call that "natural monopoly." Personally, I would call that the opposite of a natural monopoly. The term is used very confusingly. Wikipedia gives one definition, which I think is reasonable, which is basically a (theoretical or real) environment in which a single producer maximizes efficiency. But the term used by governments and their supporters is something completely different, where the government forcefully prevents all producers but one from operating.

It's silly to talk about telcos "enjoying" a "natural" monopoly, when the airwaves are one of the most tightly-regulated industries, and in addition to being expensive for a competitor to enter the market, it's generally illegal.