Blatant insensitivity and poor judgement on that big of a scale was rightful grounds to terminate that professor. Are you really defending blackface? 

Just because it doesn't offend you, someone who enjoys the benefits of not being a racial minority (I assume), doesn't give you the right to decide if or if not it's offensive to others. Go ask your black friends if they'd find you putting on blackface for a halloween costume offensive or not.

The intention of the offender doesn't dismiss something being offensive or not. Are there overly PC things that happen? Yes. But blackface is not something that's really debatable as being written off as an "Oops I'm sorry, I didn't know that was offensive." For someone who's a professor and makes 150K+ a year especially. I'd have a hard time keeping a barista on staff for that. Hopefully lesson learned and she can continue her very well-to-do career.