Has India's rapid metro expansion actually reduced road congestion?

India's metro network has grown from 248 kilometres in 2014 to more than 1,155 kilometres now, expanding from five cities to 26, with daily ridership exceeding 1.15 crore passengers. This is a substantial shift toward rail-based urban transit. Whether this expansion has meaningfully reduced road congestion, rather than simply adding transit capacity alongside continued growth in private vehicle use, is harder to establish and likely varies significantly by city.