I actually find myself somewhat in agreement with your points. You seem to be analysing history through a critical theory lens, which does yield insights. But such identitarianism fails as a structure of governance or policy. And, we're discussing DEI, which is based upon the bastard child of those academic critical theories, specifically the nonsense scholarship of nitwits like Ibram Kendi and Robin DeAngelo. (Sorry, Ibram, but reverse racism based upon race essentialism is essentially racist.)
And I still think that secular liberalism offers the greatest hope for realizing actual justice. The methods of the KendiAngelo cult (pseudoscientific implicit bias training, DEI beaurocracy, endorsement of reverse racism, punishment of dissenters) are counterproductive when it comes to realizing true justice. DEI might be less objectionable if it had more King and less Kendi.