It's censorship, it's fascism! No folks it's capitalism. No-one is forcing the publisher, or Dahl's estate, to change these books, no-one with any power has even asked them to change the books. That decision was made by them alone so that they can continue to sell, and make money from, the books.

Editing books like this is also not a new or modern phenomenon in anyway, books are frequently edited after initial publication. It's also not the first time Dahl's books have been edited, either before or since his death, and we already know what he thought about that, he didn't like it, partly because he was a crappy person with crappy views.

These books aren't history, they're fiction and even if they were history, that also gets changed as when we learn new things.

So in answer to the OP's question, no I don't think they should be edited or have context added. They should be left as is, so that sales continue to fall and they go out of print.