^ Lucas may have borrowed some superficial scenery elements or aesthetics from Dune, but really I always thought the whole Star Wars/Dune connection was overstated. The main thing is the desert planet, and offhand mentions of “spice”. These are very superficial similarities. However, earlier drafts of Star Wars featured the spice trade much more prominently - which indicates Lucas at least had some familiarity with Dune. There’s also the Jedi and the Bene Gesserit, both religious figures with super-human abilities (especially the Jedi mind trick).

But holistically, Star Wars is dramatically different. It’s a different genre (space opera versus sci-fi/political thriller), it has heavy use of robots and aliens (both absent from Dune), and it’s a straightforward action-oriented hero’s journey influenced by Flash Gordon and 1930s serials, as opposed to Frank Hebert’s heavy socio-political themes and false Messiah religio-social commentary.

Also some of the stuff Herbert complains about in the above-quoted paragraph is a huge stretch. “Hooded dwellers” in the desert? That’s a universal motif influenced by real life Bedouin tribes - not something unique to Dune. And the “sand worm” skeleton appears for like 3 seconds and looks more like a dinosaur skeleton. It’s more likely an expression of the general motif of “dead things” in the desert to visually emphasize the lifeless, hostile environment. This is similar to Westerns where we see a cattle skeleton or circling vultures to emphasize the hostile environment. Also, Tatooine is supposed to visually represent “the middle of nowhere”, whereas Arrakis is the center of the whole spice industry and a highly important world.

I mean, you may as well say Star Wars ripped off Lawrence of Arabia because it takes place in a desert and features Sir Alec Guinness wearing a robe.