mail-mark-notjunk, used by Evolution, does not really convey its purpose
The icon mail-mark-notjunk.svg, which is used by Evolution, does not really convey its purpose (in my opinion) to mark a message as not junk.
Adwaita icon in Evolution (in 4K resolution, since the icons differ in lower resolutions like full-HD)
In my opinion, the Humanity icon conveys its purpose better than the Adwaita icon.