Sustainable Architecture will vary according to time and place. What is sustainable in Assam, may not be sustainable in Kerala or in Rajasthan. Bamboo buildings might be common in Assam, but in Rajasthan, this might have to be transported for a long distance.
What was sustainable in the 1970s may not be sustainable fifty years later in 2020s. During the last 35 years, cement price has increased 15 times, while the labour rates have multiplied 30 times. The equation has changed. Then how can we measure "green architecture" based on certain points all over India and classify them as platinum, gold, silver etc. The architecture I know is very complex and it has many dimensions such physical, psychological, social, cultural, political etc.
Photo is that of the interior of a house we have designed