It was a few months ago that Keegan-Michael Key, appearing on “A Late Show with Stephen Colbert,” said he was exhausted. It was early June, immediately after the death of George Floyd at the hands of Minneapolis police officers, and he was expressing frustration with the racial imbalances — what we have come to understand, since then, as systemic racism — and seemingly never-ending inequality in this, the Land of the Free, where it is self-evident that all men are created equal. Aren’t they?