>>15032320Bounce was awful and people only used it on the bulky set if anything to stall for more leftovers recovery and to scare away a switch for Celebi or something.
Mold Breaker isn't as situational as something like Unnerve seeing as we still have tons of levitates, and tons of Gyarados sets run Earthquake.
Its Bulky set has only gotten bulkier, its sweeping sets have more starting attack and can now use STAB SE attacks on grass types without them having a free turn to run away. Electric types don't have nearly as easy of a time fighting Gyarados anymore. Even half the things it's weak to in Mega Form have to play a guessing game as what move to use. Use a fighting or bug move, it doesn't go mega, it resists the hit and just got in a free sub or worse, a dragon dance.
Use a rock move and it goes mega, takes laughable neutral damage with its better defenses, and then gets a chance to set up on you.
It's not worse than Gyarados himself unless you're running a choice set (which Gyarados almost never did thanks to Dragon Dance and bulk) or you simply don't know how to play well enough to take advantage of it.