Here's an actual link to the Wikipedia article for those that, like me, were left scratching their heads.

As the article states, this pertains only to French playing card decks, and is in fact, disputed by Snopes.

They don't use the designs anymore because someone stole the design a long time ago. I still think it's cool that they got the designs from famous historical figures.

In summary, the court cards in decks of playing cards were not initially identified by name. The assignation of identities to the kings (as well as the queens and knaves) was a temporary practice unique to French card masters that began around the mid-15th century, was not standardized for some time, and was discontinued at the end of the 18th century. The royal figures on modern playing cards no more represent specific persons than do the kings and queens in chess sets.