While I wholly understand the context in which you speak of Hindus as you do, as do the others who have commented so far, I can see the struggle within you to understand that history is NOT taught in India on parochial lines.
Nowhere, in any text book or historical account, is a Muslim monarch, dynasty or period held out for negative mention because it was Muslim. This has been internalized to the extent that there is now a tendency to move away from the traditional categorization of Hindu, Muslim and British periods of history, in favour of ancient, early mediaeval, late mediaeval and modern periods, thus leaving out the religious epithet altogether.
I agree, I am certainly not as well conversant with how history is amplified in Indian institutions. And if it is being transformed as you say it is, I believe it is a good thing.