It’s a fair question, now that so many Oscar-contending actresses have emerged from this unlikely training ground. Jennifer Hudson offered the blueprint, seguing from a seventh-place “American Idol” finish to the 2006 film “Dreamgirls,” which won her the Academy Award. In 2022, Ariana DeBose picked up where Hudson left off, winning an Oscar for Steven Spielberg’s “West Side Story” 13 years after she competed on “So You Think You Can Dance.”