The answer is more complicated than that.
Kubrick shot those films non-anamorphic, full-frame. 1.33 aspect ratio. The action was centered in the middle of the frame to be "safe" for being cropped down to 1.66 or 1.85 aspect ratio. The cropping was done at the theater by the projectionist. Kubrick apparently prefered 1.33 and wanted the DVDs to have the 1.33 version.
The debate is from those people who want the film to look like the saw it in the theater. But that was determined by the theater projectionist. Some framed it higher, some lower. They want a version cropped down to 1.78 or greater and released anamorphic to get higher resolution and fill their 1.78 screens.
Personally, I have no problem with this. I can happily either watch the 1.33 version in the middle of my screen, or crop off the top and bottom and "fill the screen". But doing so, I'd be as big a fool as those people who want their 1.33 screens filled.
If I were doing the authoring of the set, I would have used the subtitle facility to provide top and bottom black bars that people could turn on and off to crop the 1.33 down. Or put a cropped version on one side and full-frame on the other.
Kubrick was not alone in this. Willy Wonka & The Chocolate Factory was shot in the same way, as was Moonstruck.