Yes, but not always. In my country (Estonia) the biggest ISP (Telia) provides IPv6 for home connections, but not on the mobile network.

As for Reliance Jio, they have over 300 million IPv6 users, with a total IPv6 adoption of 88% [0][1].

[0] http://www.worldipv6launch.org/now-we-are-six/

[1] http://www.worldipv6launch.org/apps/ipv6week/measurement/ima...