not once in world history has a large-sized country gone into rapid industrialization mode, while also guaranteeing universal franchise or a vote for all of its citizens. When you think about it, this claim is probably true. Forget China, think about the U.S., Soviet Union, the U.K., France, Germany etc. Not one of those countries actually industrialized while everyone had the vote.
To me, this appears more to be coincidence than anything else. But there’s no denying the fact that India is one of the largest, growing economy in the developing world that has a working democracy.