Chops
Soccer Dad
I mean, sure. But on the scale of possible toxic and shitty behavior, its pretty small. Dungeons arent exactly difficult, can be easily 4-man'd and the replacement will be along soon enough. Who knows, the person who takes your place might be grateful they dont have to do the full dungeon. I know I usually am when it happens to me.Because let's be clear, you can try and justify it to yourself however you want, leaving a random dungeon mid-run intentionally IS toxic and shitty.
It would certainly be more polite if people stayed. But its akin to like... not holding a door for someone. *Barely* rude.