This is the first I’ve heard of it, but here’s one of his infamous quotes:
"There is a trait in the Jewish character that does provoke animosity, maybe it’s a kind of lack of generosity towards non-Jews.
I mean, there’s always a reason why anti-anything crops up anywhere; even a stinker like Hitler didn’t just pick on them for no reason.”
His other quotes tend to be condemnation about specifically Israeli zionism and barbaric murder, but i don’t have context as to whether he’s referring to palestine or not. Some people might have more sympathy for these statements these days, but a lot of his other quotes have to do with Jews controlling money and media, less defensible prejudice.
Here is a list of controversial actions and statements attributed to Roald Dahl:
Made numerous anti-Semitic comments, including stating there were reasons for Hitler’s actions against Jews[1][4].
Expressed anti-Israel sentiments and admitted to becoming anti-Semitic[4].
Used racial and sexual stereotypes in his writing[3].
Included racist depictions of Oompa-Loompas as African pygmies in early versions of Charlie and the Chocolate Factory[4].
Incorporated themes of child abuse, neglect, racism, sexual innuendo, and fat-shaming in children’s books[4].
Used coarse language and drug references in works intended for children[4].
Originally described Matilda as a “devilish little hussy” before editors intervened[4].
Engaged in long-term adultery, having an affair with a friend of his wife[1].
Displayed a mean and unpleasant personality, earning the nickname “Roald the Rotten”[1].
Expressed chauvinistic attitudes, frequently portraying women negatively in his stories[1][3].
Showed a lack of remorse for his controversial statements and views[1][4].
Citations: [1] The dark side of Roald Dahl - BBC https://www.bbc.com/culture/article/20160912-the-dark-side-of-roald-dahl [2] The hundreds of changes made to Roald Dahl’s books to suit a new … https://www.reddit.com/r/books/comments/1154tr5/the_hundreds_of_changes_made_to_roald_dahls_books/ [3] Roald Dahl revision controversy - Wikipedia https://en.wikipedia.org/wiki/Roald_Dahl_revision_controversy [4] What’s the Deal With… Roald Dahl? - Becandbooks https://becandbooks.com/whats-the-deal-with-roald-dahl/ [5] After family apology, 5 antisemitic Roald Dahl quotes - The Forward https://forward.com/fast-forward/349771/roald-dahls-family-has-apologized-for-his-jew-hatred-what-were-the-5-worst/
Now that I am fully informed, I have decided to continue being a huge fan of his work. Of the authors of delightful stories that I have enjoyed in my life, this is probably not even top 20 assholery.
Most of these are in the OP or other comments, thanks for putting them in one place.