Where the basis for 'COPIED,' or maybe the insinuated 'stolen idea'? Seems like different interpretations on the same subject. One idea builds off another, and it appears to acknowledge that. I don't seen any sensationalism here. Unless it's proposing that Leonardo didn't learn from others and all of his work was based off his own intellectual genesis within a vacuum.
In Leonardo's writings, he mentions "Giacomo Andrea's Vitruvius" seemingly a direct reference to the illustrated Ferrara manuscript. Secondly, Leonardo had dinner with Giacomo Andrea in July 1490, the year in which both men are thought to have drawn their Vitruvian men. Experts believe Leonardo would have probed Giacomo Andrea's knowledge of Vitruvius when they met. And though both drawings interpret Vitruvius' words similarly, Leonardo's is perfectly executed, while Giacomo Andrea's is full of false starts and revisions, none of which would have been necessary if he had simply copied Leonardo's depiction.
The author is either unaware or ignoring the fact that Renaissance artists (all artists for that matter) did not create in a vacuum, but were influnced by the masters they studied under (Andrea del Verrocchio in Leonardo’s case), and their notable peers, who were the rock stars of their day. Leonardo studied and learned from everthing contemporaries like Michalangelo and Raphael were putting out. And vice versa.
“So what’s the story here?”
Off the top of my head, I think:
Leonardo is a white man, a genius, an icon of western culture.
Any form of soiling Leonardo, can also be seen as reflecting negatively on white men and western culture.
I know, it’s a bit conspiratorial, but I do notice that there has been a lot of academic activity trying to discredit geniuses from Beethoven to Columbus.