I know of that tradition, and I believe that is true today.
In chapter 5 of Quran, it says to the people book they are upon nothing unless they implement Torah, Gospels and what is revealed from God (ie. Quran). Muslims today don't care if Islam is implemented or not. They also take some of them as authorities over others, while, it's become a plaything religion, a game of thrones and divisions.
This is while the true Master is God through his chosen ones and revelation, through his rope from himself and from humans.