That myth is completely shattered by this book:
Fernandez-Morera, Dario. 2016. The Myth of the Andalusian Paradise: Muslims, Christians, and Jews under Islamic Rule in Medieval Spain. ISI Books, Wilmington, Deleware.See this interview of Dario Fernandez-Morera here:
See also an interesting review here.
As Fernandez-Morera argues, there was no multicultural paradise. It was a society of largely mutually-hostile segregated communities, living separate lives, and where Christians and Jews lived as second class citizens subject to punishing extortionate tax and humiliating restrictions on their freedom.
Fernandez-Morera (2013) points out that life also became progressively worse and worse for Jews in Islamic Spain. For example, Jews had been forced to wear a special yellow band or badge to distinguish themselves, and there was a homicidal massacre of the Jewish population of Granada in December 1066.
By the 13th to 15th centuries, particularly after the Almohad rulers of Spain demanded the forced conversion of Jews and Christians (Fernandez-Morera 2013: 27), life became so bad for the Sephardic Jewish population in Spain that there was a mass exodus to Christian countries (Fernandez-Morera 2013: 22).
So, all in all, this society can hardly be regarded as any kind of model for the modern world.
Fernandez-Morera, Dario. 2013. “Some Overlooked Realities of Jewish Life under Islamic Rule in Medieval Spain,” Comparative Civilizations Review 68: 21–35.