I disagree I actually think it stemmed from Mansa Musa and the various Black Moors that were in Iberian Regions.
Notice once they kicked the Black moors out and they heard about spread of Mansa's Wealth Portugal Lead its crusade into uncharted waters. The dates actually line too once you look at the math
They got tired of Africans running through they region plus the untold amount of wealth from Mansa, they wanted that for themselves
Without a doubt, Tours gave them a scare.
If the Muslims and Africans won that battle, Europe's whole history would have been different.