One reason is financial. At its peak the Mughal empire was the largest economy in the world. Estimated to be about 25% of global GDP. That's close to the position US occupies in the modern world.
Mughal empire was collection of many wealthy provinces, which were wealthy even before Mughals. After assuming power most Mughal ruler did nothing but wasted wealth on countless vanity projects, unlike Europeans where rulers still funded exploration and innovation.
Yes but both the Maurya and Gupta empires have been estimated to have reached over 30% in their time.