NPR had a story on this topic years ago and the researchers they talked with said diversity appears to have a negative impact on startups but a positive impact on established businesses. The logic was startups are smaller and need to move fast and be focused so DEI type efforts distract from the main business at that time. Once established diversity help the business by having people that can see business opportunities and challenges that a more homogenous workforce would not otherwise notice.

That diversity research at big organizations has been called into question: https://www.wsj.com/finance/investing/diversity-was-supposed...