Investing in EV will improve the grid, obviously (and charging during off peak hours will stabilize it, too).

Betting on hydrogen (99% made from natural gas) does nothing to improve electricity generation and distribution in India.

Not really sure, we have our needs met for now, but most people having EVS would be a huge constraint drain on the power. I honestly feel what will happen instead is just that cars become too expensive to drive period, with only a relatively few owning private vehicles. A lot of people are surviving on 20 year old cars mostly.

Not in the us. Most charging can take place at night, using unused capacity. The only real impediment to almost universal EV use in the us is lack of easy charging for those who park on the street.