I'm fascinated by the amount of abuse the study participants seem to take without doing anything about it (e.g., blocking people, leaving groups, etc.).

Taking one example: were I a healer in a raid, especially one showing top healing numbers, and anyone started off on a slur-filled tantrum against me in voice chat, I'd immediately leave voice chat and the raid. If the response from guild mates was anything but disapproval of the tantrum, or it was allowed to happen more than once, I'd leave the guild.

There are plenty of people/guilds who don't behave like complete assholes to choose from in any online game.