My point is that Apple dominates that list of developers (and them and Google before that). How much do you think BlackBerry is contributing these days?
Since we are talking history though, one of the original KHTML devs was Andreas Kling who went on to work on WebKit at Apple and who now leads the Ladybird browser project. He lives in Sweden so I guess Ladybird is European though the newly formed Ladybird Foundation is US based (I am sure to make it easier to raise money by offering US tax deductions).