An article in The National, while correctly rejecting the Orientalist view that Al-Ghazali was the lynchpin of the Islamic turn from science, nevertheless proposes an alternative that may not be as indisputable as the article claims:
It is difficult to know how the Muslim world would have been different had it not been for the Nizamiyah colleges. What is not in dispute is that the colleges stifled scientific innovation by focusing on religious studies to achieve a political end. The colleges singularly succeeded in that task, with Sunni clerics often praising them for their role in restraining the influence of Batiniyya and in the dominance of Sunni Islam.
Wikipedia does concur that the main focus of Nezamiyeh was religion, with the other topics as less important, at least initially:
The curriculum initially focused on religious studies, Islamic law, Arabic literature, and arithmetic, and later extended to history, mathematics, the physical sciences, and music. 
I checked the article referenced by Wikipedia for that statement and it does support what Wikipedia says, but the topic of Nezamiyeh is only briefly touched in that reference. What is unclear to me is the extent of the influence of Nezamiyeh in the alleged decline of science focus in the Arab world in the 11th century. Surely judging by today's madrasas that may seem "obvious", but it might be a false analogy.