I'm not sure what you mean about the 911 sensibilities. But I doubt that 911 would have anything to do with the motivations.
What I meant is: 9/11 was a historical shock to New Yorkers so Sarai might have expected her NY friends to feel some latent discomfort, however small and irrational, towards mosques and bazars from the 'Islamic world' and to react with more affinity towards 'western' Byzantine ruins and graffiti.
It's really a question. I am asking if such a reaction would be likely or even thinkable in a youngish middle-class NY crowd or not. It's the way I do my sleuthing, if you will. I have seen your answer.
She did seem to do a lot of work with the central focus being a long structure, so if the walls went on for a while she may have liked the way it looked in keeping with her theme.
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Yes, that kind of structure could as well be the reason for her choice.