Key reason: Hindus resisted Islam with all their energies, even in times when the Islamic world had superior war making machinary and resources.
Even today Egyptians, Iranians, and Turks wonder why India did not fall to Islam. The pakthuns, rajputs, gorkhas, janjuas, gakkads, jats, yadavs, reddys, marathas never stopped resisting islam as an evil force that will take civilization to dark ages.
Dogma based certitudes such as Islam never reflect the majesticity and complexity of nature, creation and life. These are ideologies of barbarians condemned to take its adherents away from civilization and progress. Ancient Hindu view asserts differences are inherent in nature. Experience not dogma is the basis for religion. Skepticism, Critical Examining are enouraged. Feminine as manifestation of divine is accepted. Hinduism urges that change is an inherent part of the fabric of reality of the Cosmos and evolution. Plants, animals, and seasons – everything has differences, cycles built in to them. Differences are built into the way human beings are composed – in their bodies and minds and their cultures and languages. So difference need to be celebrated. Islam of course prefers differences to be eliminated and makes efforts towards this.
Here a native Hindu boy manifests native martial spirit and skills.