No, that's the one, what I mean is that this isn't the old context menu but the "move here" mini context menu. It doesn't have everything like rename, properties, etc. so it's not a workaround for "show more options" for things that aren't 7-zip.
"Some reason" here is: backwards compatibility. Good old Windows backward compatibility. If you've got habits or automations based on the Menu key (or its even older shortcut: Shift+F10), Microsoft seems hesitant to break them, even if they felt they could change the default behavior of mouse users.
