New Delhi, Oct. 21 -- In 2015, Nithin Kamath was busy making stockbroking cheaper. Mukesh Ambani, meanwhile, was preparing to make the internet cheaper for millions of Indians. Neither development appeared connected at the time, but the arrival of Jio would go on to transform the digital ecosystem that helped Zerodha grow and brought millions of new investors into India's stock markets.

The connection went far beyond two entrepreneurs appearing on the same list. Jio's affordable data, Airtel's expanding connectivity, Aadhaar's digital identity infrastructure and UPI's payment network collectively changed the economics of reaching customers online.

Kamath revisited this history in a post on X, linking his experience as a young entreprene...