Airtel used to be the biggest player and in a few short years it has dwindled to 35% customer base of Jio. The rest of them are tiny compared to even Airtel. So sure you have options for now, but its increasingly looking like there won't be in the future.

Also the original statement that Jio is the only option for a majority of Indians is true because a lot of people only joined the mobile revolution because of Jio.