There are multiple questions here:
What do the transit vs. income graphs for SF look like?
How do the SF graphs compare to the NY ones?
Is there a clustering of rich and poor stops in SF like there is in NY?
And then finally, what are the possible explanations?
Sure, they didn't answer the last question, and you have to inspect the data to answer the second and third ones, but it's okay to provide data for other people to look at.
Surely if the first question was worth answering for NY, it's worth answering for SF. You don't answer questions simply because you expect to find something, you answer them because you're curious.
Do you know the story about Richard Feynman and the wobbling plate in the cafeteria? It's another question that "nobody wanted to answer".