The slippery slope exists.

One minute you're trying to make sure you're not offending anyone.  Next thing you know, you're banning words, changing definitions, and rewriting history.

Let's look at the recent controversy surrounding the much-loved Raold Dahl books.

What's the point of editing such established works?  How does describing a fictional character as "fat" or "ugly" offend a reader? 

Where do we stop?

When both the right and left can agree, for the most part, you know you've gone too far.

Changing the work of a dead man is too far and teaches children nothing.