The main preservation of greek texts was the byzantine empire not the Arab world. If you take a second to think about it was the Greek Roman Empire. Until it fell it was the heart of the knowledge of Rome and Greece.
That’s really not even remotely true. The Empire was the primary foreign market for all the Italian merchant republics.
They almost always had a significant presence in Constantinople and in later periods almost controlled internal trade in the empire.
The Venetians especially were highly reliant on their trade with Constantinople until quite late.