In some fairness to Revere, engraving black features was hard and perhaps beyond his skill.
I've collected some wood cuts and unless the engraver was very skilled a black person looked like a blob (no facial features) or a had grotesque exagerated features.
That said, Revere was a great silversmith and a freemason, and he should have done/known better, or at least tried.
In follow up, I believe Revere and Atticus were fellow freemasons and had to know each other, which makes his ommission particularly bothersome to me.