Mate is a beverage found in much of South America. While it is uncertain where mate was first made, there are more varieties of it found in Paraguay than anywhere else. Also, mate is used more widely there than anywhere else. Ttherefore, Paraguay is likely the place where mate originated.
If true, the statement that it is rare for there to be a great variety of types of a beverage in a place where the beverage has not been in use for a very long time would most strengthen the argument.