Black people were not the only slaves and things were a lot more complex. Persians, Europeans, other Arabs ect were enslaved by the Arabs ect.Slave raiding raiding by Europeans was negligible. It's nothing like the Indian ocean slave trade where raids into the interior played a huge role in the procurement process for the non-African slavers.
The Trans-Saharan and Indian ocean slave trade of blacks predated the trans-Atlantic by 1000 years+. Kinda wild to say the Trans-Atlantic slave trade was the first time slavery was racialized when even at the time of Mohamed Abeed was synonymous with black. Those trades were so prolific every muslim in the MENA has sizable amount of ancestry from (female) black slaves that arrived from those trades. Speaking of brutality, these Asians employed systematic unhygienic castration of male slaves such that only ~10-33% males lucky enough to survive the process in those slave trades made it to their end destination. Western Africans built warring empires, syndicates and trade networks for the explicit purpose of producing slaves to meet European demand and ultimately enrich themselves. The attempts to absolve West Africans from their complicity in the trade is wild.
They also didn't believe in the one droo rule in which black blood was seen as tainted ect. A Sheikh could have a son from a black woman with dark skin and black features and that child will be seen as free and inherit everything of his father.