Is India lacking in variety? It has more languages than Europe.
Variety isn't a bad idea in and of itself. But you're making the mistake of assuming all the people who live inside a particular nation's boundaries are the same.
The majority of Indian immigrants to Canada are coming from one state, Punjab, so the benefits of diversity within India is not necessarily reflected in the Indians coming to Canada.
India as a whole is diverse. Canada is NOT getting immigrants from all of India but rather from 2 states (mostly one). Please learn about the issue first.