Now I know what "save your candies" for
I am out of magikarp candies...used to have 2000 but evolved them all. Damn
Answers
What if u have caught a shiny magikarp but no candies to evolve? What if it's also hidden in dratini (or others) but u have just evolved a couple Dragonites? Seriously how can u so sure it's not related to that message? Might not be related to what he said but now I just "didn't save enough candies" to evolve a shiny gyrados, in case I am lucky to catch a shiny magikarp.
From the look of it, you will get to 400 Magikarp candies in no time. Seriously, I'm looking to get at least a few Gyaradoses out of this event. People who come into this event with zero Magikarp candy will walk out of it with at least one Gyarados. Same goes with other water Pokemon.
Plus, why would such a generic message be about a specific species? At the end of the day, I'm sure that dude just blurted the sentence out of nowhere and is now regretting it. Who knows, if you check Niantic's employee roster, that guy may have already been fired.