As an arab muslim guy I can say that it exists, when I was a kid I read some stories about ppl asking for loans in small/medium/large cities ( Not in berber communities since they were communities ) also Medicis family asked for 20K ducas loan to a morrocan king so ...
But there are many ahistorical things in the game :
-Jizya was a tax on non-muslim ppls you're not supposed to loose piety for this + that North african countries were very tolerant and had 1/10 of their population as non musmlims ( Or at least that was the case in Morroco )
-Ceuta was/is a very very small port/city far from the 8 base tax of the city
-Casablanca didn't exist
-Many of berber countries were just full of vassals since they were formed by tribes and it was hard to control them, and some times the king even gave independency to some cities like Salé Capitol of barbary Pirates ( That actually stole a lot of trade from America so GIVE US A NODE PLS)
And I can make 6/5 other points about how Morroco AI is wrong and how North African countries are not well designed ( For example almost every morrocan king was a son of a women from the harem so we had a Georgian king a Black king etc ) , but it's a game and developpers can't do full focus on every state/religion so ...