John Simon, who has served as PG&E's executive vice president and general counsel since 2017, will serve as interim CEO. In a statement addressing the leadership changes, Richard C. Kelly, Chair of the Board of PG&E Corporation, thanked Williams for her "service and tireless commitment" to the company and recognized that "tremendous challenges" lie ahead for the organization.
Investigators linked 17 wildfires to the California utility company's equipment in the year Williams became CEO, according to Fortune. Just hours after her departure, the company announced that it will file for Chapter 11 bankruptcy protection due to the financial impact of the wildfires.
Williams' exit highlights a persistent problem in corporate America, where very few women, and even fewer women of color, hold leadership positions. When Williams first assumed the CEO role in 2017, there were 32 female CEOs at the companies on the Fortune 500 list, the highest number in history. That number has since decreased, with just 5 percent of Fortune 500 CEO seats now being held by women.
In a CNBC Make It interview for Equal Pay Day last year, Lisa Crooms-Robinson, Professor of Law & Associate Dean for Academic Affairs at Howard University, said that the lack of women in leadership roles, especially women of color, certainly affects the gender and racial pay gaps that exist today.
Women earn, on average, 80 cents for every dollar earned by a white man. Among women of color that number is even lower, with black women earning 63 cents for every dollar, Native American women earning 57 cents for every dollar and Latina women earning 54 cents for every dollar.
"For most organizations, [closing these gaps] would require a shift that goes beyond diversity committees and affinity groups," said Crooms-Robinson. "Committed organizational leadership at the very highest level is essential to make such a significant culture shift."
In an interview to accompany Time's list of women who are changing the world, Williams spoke about what it meant to be the first Latina in her position and the impact that she hoped it would have on young women in the future.
"You always hear people talking about what it means to be the first," she said. "But I think it's important that we focus on making sure there are others. While I may be the first, I certainly don't want to be the last."
Like this story? Subscribe to CNBC Make It on YouTube!
5 black women talk starting salaries, being underpaid and how they asked for more