The anonymity of the internet has caused many interesting social phenomenons, chief among them is that people are free to create their own persona and identity.
Most competitive gamers have an identity that they use in-game. This name sometimes has a lot of significance to that player, sometimes players choose names on a whim.
Some use these monikers to sound overly bad-ass. Kind of like that 10-year-old that screams at you while playing Call of Duty with the name xXxLAG_SNIPA_420xXx from clan Shadow Tiger Ninja Pirates.
Fans know the lineup as Hauntzer, Svenskeren, Bjergsen, WildTurtle, and Biofrost, not Kevin Yarnell, Dennis Johnson, Soren Bjerg, Jason Tran, and Vincent Wang. In fact, only the most hardcore TSM fans could probably even use their real names offhand.
Now, this isn't an appeal to dropping nicknames and monikers altogether. Gamers gain a sense of identity with their online persona and this certainly isn't trying to dissuade that at all. In fact, monikers should be used interchangeably with real names but real names are very important for a number of reasons.
Sports, and by extension esports, are definitely forms of entertainment. However, the players who compete are deadly serious about becoming the best players in the world and making a long term career in their games. Thus, when esports only uses monikers, it sets up big personalities to be more characters than human beings.
Esports is not the WWE. This is no disrespect to wrestling fans, that's just a distinct, different form of entertainment. Esports should not be scripted and be purely about the drama and storylines of the characters. These are actual athletes competing to be the best. Using their real names humanizes them and their stories.
ELEAGUE does this particularly well in their CS:GO broadcasts in regards to casters. The personalities interchangeably refer to each other by their first names and their monikers. This creates a more friendly and approachable atmosphere.
Hopefully this will eventually extend to last names of players just like in traditional sports.
In real life, good friends don't greet each other by their monikers exclusively, that's just not a thing people do. Does it come up occasionally like a nickname? Of course it does, but friends don't usually shout, "Hey xXxLAG_SNIPA_420, how are you doing this fine day?"
Real names don't have to be used exclusively, but throwing them in makes them more like athletes and less like cartoon characters.
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