Context, they are looking for a party for a raid (Ice Crown Citadel - 10 or 25 person content) in World of Warcraft circa 2010. Gearscore was an addon to quantify/auto-inspect players to make sure you could actually do the job. Also they are playing a damage class, so there are a lot of players in that pool.
I miss those days, nostalgia is one hell of a drug.