The problem with LTF on this card is who in their sane mind is gonna give a card with a yearly free business class voucher and Vistara Gold FOR LIFE. It is very uncommon, almost unheard of for any Frequent Flyer program or credit card.
That's shooting themselves in the foot as it devalues their own loyalty program and even business class product. If the bank is paying Vistara for it I wouldn't be surprised, but definitely not in the interest of the airline to give free cards. They will definitely not like it.
Anyways that's for the business to decide.
I hope you were mindful enough to ask your brother before posting because he might get some flak from the bank, specially once people start flooding Axis which such LTF requests and pointing it back to your post.
Moreover this is a PUBLIC forum, not private or hidden from even non members. It shows in Google and it might get archived as well by other third party web services.
Specially in a bank I wouldn't be surprised AT ALL about the employee handbook or internal policies having something against what you're publicizing here. So better check with him before it gets back to him.