There is still something of a mismatch between the threat and the defense, in that the phasers fire very rapidly, but the missiles move somewhat more slowly than the "classic" threat of photon torpedoes. It seems to be no contest.
Yet Robau's crew never seemed to think that firing back at the projectiles would be necessary - it was a shock that the shields did not handle the threat. So there might be no culture of active defenses in Starfleet despite the demonstrated capacity.
And when the weapons were
used, admittedly by a badly damaged ship, they proved quite unsuccessful. They were 100% successful against threats directed at a third party (shuttles in teaser, Spock in climax), though. Perhaps this sort of defense really is useful only against inferior threats, and the TOS examples and STXI aren't that different in the end?