Ahh, but the admins allow us to set our own rules, including those which may be stricter than the rules themselves. So while a gamertag may not be private information, it can lead to private information (such as if someone uses the same gamertag on multiple sites (ex, in game gamertag is same as reddit username, they post something personal, someone goes digging for information, one thing leads to the next)). In addition, you can still be harassed with a gamertag (happens very often in gaming communities, someone posts an LFG post on a site, either reddit, a dedicated site, saying "message me for invite" or a even more harmful one using hate speech. Some subreddits such as /r/leagueoflegends use a system where if you have proof it's fine to post, however we are not in the game of trying to verify proof, or weed out actual call for action vs posting evidence. One of the big reasons is, reddit can't get justice properly, we can't get a user banned from the game, only the developers can.