The context menu tab in Dolphin’s configuration lets you toggle context menu items. For some reason, some context menu items are omitted from this settings panel meaning you cannot remove them. For example, cut, copy, paste, rename, etc.
I’m not sure what you are getting at here…
Are you saying that if you use a GUI program, you don’t use keyboard shortcuts?
Reducing clutter in context menus like this makes it much easier to find things.