Comment by int_19h

There are many discussions on this exact topic online.

TL;DR: while Dune has many references to various concepts coming from Islamic societies throughout, the Fremen are the obvious stand-in for Arabs specifically, and so get the most attention. And, in the context of the first book at least, Fremen are the "good guys" in many ways - if you reframe it in modern terms, they are the natives fighting against a colonial empire that subjugates them in order to extract a valuable resource from their lands, and then on top of that there's also the more subtle ecological angle.