While I think the world is enriched by people who get joy from their partners having crazy sex with others, cuckoo birds are a menace to all of aviankind, to the point that they other birds will hue and cry to chase them out of dodge.
Outside of a kink context, its use is a pretty great indicator that the person using it is a hateful moron who thinks they're"winning" if someone is "triggered." Basically the online equivalent of a pair of truck nuts.
In that respect, I'm grateful for its prevalence as it saves me a lot of time/energy that would otherwise be spent dealing with assholes.