Almost entirely, the existence of Chief Diversity Officers - and to a lesser but still prevalent extent, this "off-to-the-side" teams you mention - are just jobs programs with an identity politics twist.
CDOs exist so that the "right" people can have a high-power (even if only via public perception), well-paid C-suite role. These ethics teams exist so that a group of the "right" people can level up their resumes. Instead of being a developer at a bank in Omaha you can be on the AI ethics team at a startup. Instead of being a developer at a startup you can be on the AI ethics team at a FAANG.
CDOs exist so that the "right" people can have a high-power (even if only via public perception), well-paid C-suite role. These ethics teams exist so that a group of the "right" people can level up their resumes. Instead of being a developer at a bank in Omaha you can be on the AI ethics team at a startup. Instead of being a developer at a startup you can be on the AI ethics team at a FAANG.