The hairstyle change was a big deal. Wikipedia:

Moore became one of the most fashionable (and highly-paid) stars of the era and helped popularize the bobbed haircut.

Let's see how her career turned out:

Moore took a brief hiatus from acting between 1929 and 1933, just as sound was being added to motion pictures. After the hiatus, her four sound pictures released in 1933 and 1934 were not financial successes. Moore then retired permanently from screen acting.

After that it was poverty, vagrancy, and an ignominous end in a rooming house. Just kidding! She made good money managing her investments, became a partner in Merrill Lynch. In her spare time, she did . . . this.