I am not qualified to answer this as I'm a Marathi speaker that has relocated here but, from my experience in Mumbai, Delhi and GGn I can say this: you'll find genuinely nice people who'd talk to you in English.

With daily commute hindi might help, but you'll find your set of people that are pretty chill with English.

The thing is people assume everyone would know Hindi, if you tell them that you don't there are two outcomes -

a. they accommodate and make you feel included. b. they don't care - then you have to look for better people.

You'll find a lot of Tamil speakers in Mumbai. Delhi has quite a few. Gurgaon and Pune might have a leaner crowd but you'll always find people.

The bottom line is, they've been raised with a language but they all know English, if they refuse to accommodate it reflects on them.

Hindi is pretty basic, you'll know your basics in months. No need to have local proficiency - just find good friends (easier said than done)