Look, I monitor the activity of both the main wiki and the Discussion app, partly because I'm the only admin/moderator active enough to do so.
In the section on User Conduct, one of the rules was
that you cannot "Solicit personal information from any user under the age of 18." This essentially means you can't ask anyone directly for something that can considered private information, like say, a Gamer Tag.
Since this is clearly still happening, from this point onward, I will be less lenient on anyone who asks such a thing. It's one thing to post your Gamer Tag and other personal information in your Bio, which is fine since you're giving this information voluntarily, but here specifically? A flat no. Do not ask this "here". If someone has a gamer tag and specifies which platform, ask on that platform, not "here".
To summarise, this app is for discussion. Not social interaction. You can give information, but only in your Bio. You cannot ask for information in any shape or form. Offending users can be blocked or even outright banned without further notice.