Agreed it's not clear from the article, but I think the reason is the similarity to an engraving called the Droeshout portrait [0] > It is one of only two wor

Agreed it's not clear from the article, but I think the reason is the similarity to an engraving called the Droeshout portrait [0] > It is one of only two works of art definitively identifiable as a depiction of the poet > ... commentators have used the Droeshout print as a standard by which to judge other portraits alleged to depict Shakespeare. [0] https://en.wikipedia.org/wiki/Droeshout_portrait https://en.wikipedia.org/wiki/Droeshout_portrait