“it’s their fault if they get offended”

• person who doesn’t value the opinion of those they offend

This is wrong. What OP said was very much offensive, comparing yourself to that of a slaver. It is a rare figure of speech, and while not intentional it is still offensive. However, the context of who you’re talking to doesn’t matter, it is an offensive statement regardless of the history of the person you’re saying it to.

For OP: it is okay to make a mistake, especially when you recognize it.

Both of those terms are offensive in the US, too. People that use it just choose to not value the input from those that they offend.

It’s not the tuition, it’s the funding being cut by the states that’s the problem (for public universities). States used to fund universities significantly more than they do now.