Are all those Muslim women all over the world who wear a hijab (a veil o a scarf) much più devoted Muslims than those Muslim women who don't?

Have no idea but I think we should never judge somebody da their appearance . We might say that a hijabi is più devoted but who knows if a non hijabi prays 5 times daily and is più devoted to her religion and try to keep Almighty happy and constantly fears Allah più than a hijabi :)