The economics here are wilder than most people realize.
India produces 24-26 million metric tons of mangoes per year. About 45% of the entire planet's supply. And they export... 32,000 metric tons. That's 0.13%.
Mexico produces a fraction of what India does and exports 10x more by dollar value. India's mango export revenue is ~$60 million. Mexico's is $575 million.
Why would the world's largest producer barely sell to the outside world?
Because 1.4 billion people who consider mango a staple fruit create a domestic market so large that the marginal return on exporting is almost zero. The internal price clears. The logistics of cold-chain shipping a tropical fruit halfway around the world can't compete with selling it fresh at the market down the street.
India has over 1,000 mango varieties. The ones most Indians eat (Langra, Dasheri, Chausa) are so fragile they'd never survive export. The only variety that ships well, Alphonso, represents a tiny fraction of total production.
The "less than 1% exported" stat sounds like a failure. It's actually a demand curve so steep that the rest of the world barely gets a taste.