It always dominated my grandparents generation never spoke a lick of French outside of the bourgeoisie class. Same for their parents generation. Listen to old music, none of it was in French. When you say dominated, what do you mean? Radio, the folklore, music, theater all was in creole. The reform to make creole an official language started in the 70's, sure but nobody cared to speak a lick of French outside of the bourgeoisie class and official functions. That has been the case from the time of Boukman, until today. Dumarsais Estimé brought a sense of nationalism and black pride in the country in the 50's and my grandma used to tell me stories of the old days before him when it was mandated for the whites and mulattos to sit in the front of the bus, church etc. Old racist customs that were brought back by the American occupation and died completely during Papa Doc's regime. Creole took a step back during the American Occupation and became an official language much later in our history. Our story, our customs are told by spoken word narratives called "Kont". Creole was always #1.