I think that there is much in way of truth in the quote. Changez's journey in the novel is one in which his sense of identity occupies central importance in his life. His rejection of the identity that was socially conditioned is essential in this process. He rejects the wealth, the trappings of financial security, the power of his work at Underwood Samson, and even his love of Erica in the name of his own sense of self. The journey he undergoes is one to find his own identity.
The embrace of an identity that is more fundamentalist and greater in its opposition to "the West" become part of who he is. The narrative is driven with the tale of this reclamation. In this regard, Changez's identity is more fundamental and more basic than all other external realities. Changez rejects all else in the embrace of finding his identity and making peace with it. By the end of the novel, we are not entirely certain if he has succeeded in this. Yet, it becomes clear that he thinks he is closer to being content with his identity as who he is than who he used to be. As identity is shown to be a complex issue in which no specific answer can be immediately discovered, it becomes the basis of his being and more fundamental than money, power, and love.