This is not a functionality bug, but rather a mislabeling in the system. As you see, when you go into the Element - Image area of the Theme Styles, all of the labels are “icon”.
UPDATE
Actually, the image element theme style doesn’t work either … I tried adding both an icon and an image element and then I used the theme style editor for the element - image, and nothing is happening. I see icon block, but that seems to be something different, as well. Not sure what the issue is, but I can’t get any of these settings to work.
Have you ever tried what the settings are for? If so, you would have seen that they only affect the icon setting on the image element and are therefore named correctly
Also, so there is no global image element styles? You have global styles for an icon on the image, but not the image as a whole? That’s also something I’d remedy.
No worries. You can use custom CSS or a global class if you want to apply the same (default) styles to every image, which is basically nothing else than the theme styles