India never banned Bitcoin -- it was always legal to use and trade it. What happened was their central bank banned regulated entities (banks) from dealing with cryptocurrency businesses like exchanges in April 2018. That effectively killed the centralized exchange infrastructure. It made it impossible for people to deposit INR with a bank account to buy cryptocurrency.
The ban being struck down is a major victory, but it's still frustrating that the central bank held back the industry for two years. And they are still fighting this Supreme Court decision too.