Correct me if I misinterpreted what you've written, but if you think removing diversity is what the "silent majority" wants, boy, are you living in a delusion. You might be trying to make up explanations to forcibly rationalize bigotry. Ethnic and religious diversity is not something you can just turn into "homogeneity" without large-scale genocide. Besides it was never a significant factor in Japan and China's growth relative to India.
I certainly agree with you that not everyone's proud of India's diversity. It's been more of an issue lately where we've a separate "Personal Law Boards" for certain religious groups and at the same time we call ourselves secular.
If India has to really become a secular nation, it has to make sure that it treats everybody the same without any specific laws for specific groups.
But perhaps you're not that into consistency, in which case I can empathize why you're okay with the status quo.
Also, please don't generalize. Not everyone is "proud" of india's diversity. I much prefer how the homogeneity of countries like Japan and China has enabled them to quickly progress. I believe i represent the views of a silent majority in india.