Earlier quoted context omitted.
How much evidence would ever convince you? How much evidence of racism do you need? How about red lining that continued until the 90s which locked black families out of home ownership? There is so much evidence available that demanding evidence at this point is more a sign of willful blindness than intellectual rigor.
I think he's asking for evidence of Google's racism, not racism in general. Google can't 'fix racism' to hire more African Americans, they can only prevent it in their hiring process.
Then we get VCs pledging to take deliberate steps to address the problem and they turn out to be vaporware.