Data point: My partner got his boarding passes and boarded JFK-AMS-BOM. Price was US$1900 one way in Delta One, connecting to KLM Business Class. Bought with just 3 days notice. Very happy with that.
No question asked in terms of eligibility to fly, just was asked to produce the required paperwork (Health Declaration, Vaccine info, Covid test results from last 72 hours, and other paperwork required by Netherlands and India).
Thanks for the help on this thread!
I will update later as to the extent of BOM arrivals' required testing and possible quarantine.