I have a lot of friends in mixing and editing who insist on using that one child laughter sound effect. I mean, we're talking big blockbusters, multi-million dollar films that use it and I'll tell you why.
It's so fucking obnoxious to hear that "hahaha? hehe aghhaha" and that's the point. It's become a running joke behind the scenes. Things like your Wilhelm Scream are made to be referential but this giggle is still used today, buried in mixes, all because it's a funny gag the sound editors like to toss in. At screenings, it's not uncommon to hear people snickering when it pops up. It's meant to be aggravating, and that it is.
https://youtu.be/ih4ye0c9p34
Here's the effect for reference.