Oh man,What a piece of bullisht! comming from what was a respected medium in the past like the BBC.
There are some people that believe that millions of people could have died because of the illnesses coming from Europe, that at the same time came Asia and Africa as they are united. To say that those people were killed on purpose is a piece of sht, and propaganda without proof.
Not to mention the 50 million that is absolutely outrageous. Not even the British and North Americans(now US and Canada)native extermination had such high numbers, and that was on purpose("the only good Indian is the dead Indian" founder's fathers quote) and using technology available in almost 20th century.
Spaniards and Portuguese in 1600s were very small numbers and technology was more advanced but not that much. They conquered South America with the help of native tribes, something that is well documented.
And the queen of Spain made native Indians that had baptised by law equal to Spaniards. Something that people in the USA only made in the middle of 20th century with Indians, Mexicans(from conquered territories like California) and black people.