Should I include challenges I faced on account of my caste in my diversity statement? Some of the graduate programs in US schools require you to submit a diversity statement as a part of the application. I have looked at some resources on writing it, like these ones.
I happen to be from a lower caste in India. Hence there are specific challenges I had to overcome to make it to college. I am not sure if I should talk about it in my diversity statement because
there are quite a few professors from upper caste community in the departments I'm applying to and I'm afraid if mentioning my struggle will rub them up the wrong way. Is it a good idea to talk about my background in a diversity statement or is it better to leave it out?
Your diversity statement is not about who you are.  It is about why you should be admitted to the degree program.  In particular, it is about your ability to work with other people in the degree program and your later career, and how this ability will advance the goals of the degree program.
If your experiences relating to your caste has prepared you to work with other people, including perhaps disadvantaged people, then yes, write about that in your diversity statement.
The fact that there are upper caste faculty in the department is not very relevant.  Faculty overwhelmingly come from a higher status background than applicants.  There will be many applicants discussing experiences that are unfamiliar and uncomfortable to faculty.  Avoid stereotypes and personal attacks.