I admit the Playmo-version trousers are a bit wide around the knee, in comparison with the historical dresscode-examples.
Such trousers were indeed wide (so like the Playmo-ones) in the 16th and 17th century, but got steadily narrower around the knee (buttoned up) during the 18th and early 19th century.
Low-rank common sailors/pirates often carried them unbuttoned at the knees and thus loose... The playmo-ones with the white stockings for officers are based on the "common sailor"-kneepants, which were released with the previous update of the pirates-theme.
Btw, though I'll be 40 next year ( ) I still like wearing loose-fitting jeans! (at home usually low & baggy, like I'm still a youngster )