It should always show its current state. If a button is doubling as a status display, it needs to display current status, that's the entire point of a button doubling as displaying information.
Would you flip a breaker to the "ON" position in order to turn it off, or would you expect the breaker to display its current state of being ON/OFF?
Would you flip a breaker to the "ON" position in order to turn it off, or would you expect the breaker to display its current state of being ON/OFF?