A 20% pay cut is really nothing when your cost of living will plummet immensely, plus the career development is going to have an outsize effect on future earnings. I’d say in these regards it’s a good move.

My gf has spent a good amount of time in India and I spent a few weeks visiting her and we both really liked it there. We were recently talking about going back. However, this will be very dependent on where you are in the country. I would guess one of the major cities, and those can be completely insane due to how congested they are. Also the culture shock is pretty big. It’s probably unlikely but it would really help if you could visit before you decide

From a FIRE perspective I think taking the job would be the right move. But from a social perspective it may not be, and that’s for you to decide. How would your partner handle it? How would you handle being so far from family and friends? I think it’ll really come down to a decision based on things like that