Why is it that most of the brilliant philosophers are Germans if the history tells us that philosophy came from Greece?

Why are the best tomato-based pasta sauces Italian, if history tells us that tomatoes came from the Americas?

2500 years is a long time; and in at least some ways, what the Germans were doing with philosophy in the 18th and 19th century was far from what the Greeks did in the 5th century BC (though unlike other disciplines, maybe not far enough!) At any rate, just because a people invent a field of endeavour, does not mean they get to dominate it forevermore. Cultural artefacts aren’t genetic.