It's not good enough. Referring to black people in those terms may have alienated a lot of people ... but it will also have reinforced that behaviour in others. Because Hogan has been a role model for millions for decades. We literally have people on these forums basically saying "Hey, Hogan uses that word, so I can tell everyone that I use it too! Of course, I use it in private as well, so that's 100% fine."
The thing is, "private" is only private until the wrong person overhears you. It's not the fault of the guy that filmed Hogan, that Hogan went on this verbal assault of all African Americans. But the fact that there is a video of the conversation, by definition, means that it's not "private".
Think about it. If your girlfriend had a "private conversation" with her friend saying that you're a useless, ugly a$$hole, and that you are shyt in the sack and she is only with you until she finds someone more intelligent with a bigger dikk ...
Do her comments have less value because she thought you couldn't hear?
Does she MEAN them any less?
Do you forgive her because she said it in private?
To me, the principle is exactly the same. The fact that he was in "private" led him to think that he didn't have to pretend he's not racist. He LITERALLY SAID "I am racist".
That's why a trite apology and just keeping quiet for a while isn't going to cut it.