It is necessary. There’s nothing here that distinguishes you from the thousands of international Asian students who get rejected when applying as freshmen.
You got rejected by all of these schools the first time around, so what distinguishes you and would make them want to accept you as a transfer? Learn how to take a hint.
When transferring to elite colleges, you need to provide specific reasons as to why your current educational institution is not meeting your academic goals and simply saying you want something more prestigious will not cut it especially seeing that you are going to the top school in India for your desired field.