New leadership? He took over when it was engulfed in flames (he’s just the scapegoat), they need to clean up above him. This is a CEO and board problem, who let this run rampant for over a decade.
That's optimistic. To that kind of institution, what matters is getting back to business as usual with as little disruption as possible. They'll just hope that firing a scapegoat will appease the mob long enough for them to move on to another scandal, and if that doesn't work they'll keep firing scapegoats until it works.
Actual company culture changes would require that the people at the top have incentive to change. The higher ups at Activision-Blizzard already showed they were willing to tank the company's long-term potential for short-term profit.