From the TMZ article:
Wallen tells TMZ, "I’m embarrassed and sorry. I used an unacceptable and inappropriate racial slur that I wish I could take back. There are no excuses to use this type of language, ever. I want to sincerely apologize for using the word. I promise to do better.”
I'm not going to stand here and pretend that I didn't used to be a fucking racist when I was a kid. I made a conscious choice a long time back to change that, and it's work. But you know what's not work? Keeping your fucking mouth shut. That shit is easy, whether you're sober or not.
Best case scenario, this incident was a wake-up call for Wallen, and he's doing the work. I seem to recall that Drake's judgment isn't so great, so their being on stage together doesn't say a whole lot.