The western Mediterranean is a huge mix anyways. Spanish has many words of Arabic origin. Darija has many word of Spanish origin. Spanish ojalá for instance is just inshallah. Italians and Spanish usually can speak with each other in their respective language. I had a conversation once with a Moroccan living in Italy using my poor level of Spanish. Southern French youth is increasingly using Arabic words learned from the Diaspora.

I wouldn’t be surprised if the mix ends up with a new common language being formed in a few centuries.