Without contesting the other reasons for Spanish anti-Semitism, it is significant that from the time of their expulsion till today Jewish written records extoll the civilization and glorious achievements of “Al-Andalus”/Islamic-Spain - while Christain records (till only recently) only lament their persecutions & celebrate their resistance.
Did you ever ask how was it that Spanish Christians in Islamic occupied “Al-Andalus” did so much worse than those wealthy Jews they resented.
The Moores, for a time, were tolerant of Jews, who were the educated professional class and therefore useful. Maimonides and the poet Judah Halevi were among the luminaries who for a time thrived under Moorish rule, both as court physicians and advisors, though in the end Maimonides had to run for his life, and Judah Halevi was drawn inexorably to the Holy Land, where he was murdered (by an Arab just for the hell of it) while kissing the ground at Jaffe Gate in Jerusalem. The Christians who resented them were the peasantry, who remained faithful to Christianity while their “betters” most likely accepted Mad Mo. When the world turned over again, and the Moors were on the run, the aristocrats found Jesus again, and the Jews continued to make themselves useful to them as the educated professional class. Nachmanides thrived as Maimonides had before him in the Christian era, though in the end he also had to run for his life to Israel. His grave is believed to be on the Seventh Step of the Cave of the Patriarchs in Hebron. His synagogue in Jerusalem has just been rebuilt from an abandoned ruin a few years ago.