If it is a human finger on a button making the change then just the touch will take a very long time in Arduino cycles.
But the button itself will present another problem if it is not hardware debounced. The contact is not clean. Arduino with good code will see maybe dozens or more press and release events (the bounce) for every touch. The interrupt will catch them all, for all the good it will do.
If it is not a human and/or button but rather something very fast or fleeting, interrupt is justified. But for humans and sloppy inputs the first question I think is "why?".