The 1920s saw America booming, Clara Bow & Louise Brooks represented the era of the Flapper to millions. The term "It" Girl began with Clara Bow starring in the film, "It" in 1927. Even so, both Louise & Clara already had "It" before the name stuck.
Clara Bow made over 50 films but "Talkies" were a problem for her. Her thick Brooklyn accent did not transfer. Clara had a hard life as a child and again after her career ended. She suffered through both money and relationship trouble. Her mother was declared legally insane. Mom had attempted to cut Clara's throat when Clara told her she wanted to become an actress. That's what I would call "lack of support."