In the heat of moment, we all say and do something that we end up regretting.
In response to the admission, the outrage is palpable and expected.
Is racism wrong? Absolutely. I don’t know him personally, but it sounds like it was an emotional, knee jerk reaction that under normal circumstances might not have happened. I am not African-American, so I cannot and will not tell someone who is how to react in this situation. From my perspective, he sounds contrite and remorseful. While his apology may not make up 100% for what the actions he was thinking of undertaking, it goes a long way in showing that he is changed man. For that, it is enough for me.