“allow me to write that Darwin’s accomplishment was a spark of genius”
Darwin’s ideas were mostly if not completely borrowed from others before him, going back at least as far as Lucretius in the first century B.C.
And Einstein borrowed heavily from others. But there was a spark of genius to see the data in a way no one else had seen it. That Darwin took his notion too far is not a detractor from the genius he showed. It just indicates that even a genius can get it ‘no so much’ in the end. Human arrogance seems to get in the way with many geniuses.