In reality that never was a thing. Qualified people have been overlooked for decades. In Blizzard’s case they underpaid and refused to promote a whole group of qualified people. They also assaulted and harassed them.
A lack of diversity isn’t the root of their problem. It’s poor management and just not caring about anything other than their quotas and the bottom line. You can see that attitude in the games they produce.
They don’t care about their employees anymore than they care about their customers.