I don't know how many times you have activated approach and yet you failed to notice what happens. When you activate approach the speed target Vapp appears in magenta at the bottom of the speed tape and that is what you are supposed to check.
It won't necessarily appear as it is not necessarily what you're looking for by activating the approach phase.
Calling the color of the altitude target is good procedure but calling the color of the speed is too much especially when "managed speed" and "selected speed" are the appropriate calls.