Let us take one out of numerous important points in your argument: 

“It's [Sanskrit is] part of everything that has to be fought over

to protect the diversity and inclusiveness of India, its secular state and its

egalitarian Constitution.”

How to say this in Sanskrit? 

Several possibilities, here is my proposal: 

संस्कृतं भागमेव सर्वस्य योधनीयवस्तुनः, 

भारतस्य नानाविधत्व-व्यापकत्व-लौकिकत्वानां च तत्साम्यलक्षितसंविधानस्य च रक्षणार्थम् ।