When it comes to naming conventions and abreviating the Console names the
Xbox One ended up going the route of
XB1, though the XBone had some traction at first and there was possible alternatives such as Xone & Xbox1. In the end XB1 also worked out better long term by expanding well enough with the subsequent releases with
Xbox One S being
XB1S and
Xbox One X being
XB1X. And if you want to count it, amusingly enough the
Xbox One S All-Digital ending up as the
XB1SAD
But for the Xbox Series X I'm not sure which way it'll end up going and am curious about the popular opinion as I feel like it could go multiple ways since there's various valid arguments and from what I can tell MS hasn't taken a public stance. Priority could be put on fitting the 3 character baseline, accommodating potential subsequent releases or being more careful to not overlap with the Xbox One abbreviations (ie: XBX could be taken to mean the Xbox One X)