Comment by wpm

Mouse affordances don't usually ruin it for keyboard preferrers. Keyboard shortcuts and control are often an afterthought or downright written off because "they can just click" but thats down to laziness or lack of care than some hard and fast rule. However, a keyboard affordance is usually invisible, and a mouse affordance isn't, so they can very happily co-exist without affecting one another. For instance, the Alt modifiers in menus in classic Windows, those have almost no effect at all on anyones ability to click the menu item with a mouse.

Touch affordances and UI does have to be visible, and there is only one screen. So the touch affordances and mouse affordances are mutually exclusive: targets get larger, padding expands, UI gets dumbed down, etc etc.