What "until"?
It's just Activision.
You think it’s all Activision’s fault until you learn that Blizzard was toxic from the get go. Blizzard products had issues before Activision bought them, they cut content for time, overworked & underpaid people, killed what could have been great games, all on their own.
Activism is just a corporate scapegoat for the mess Blizzard has always been. Separating Blizzard into its own company won’t fix any of its problems.