I could probably understand suing for ripping off a fully choreographed routine from a whole music video. it's pushing it a bit to sue over a short dancing emote... Unless of course the the holder of the copyright could also show this infringement has impacted his business financially as well?
Potentially if you are a god at dance, you could make a killing at creating and selling popular and trending emotes for games like fortnite. (then sue any company that copyrights the moves).