Ah, one of them came out.
"Phone numbers are an ancient concept and we're used to them." Say no more. We're all used to numbers, including friend codes, bank accounts, driver licenses.
Email addresses that vary so much are annoying to look at/write/pronunciate/handle for any first time exchange in the absence of Cut&Paste, which is common with many forms of exchangeable communication IDs, so your example leads nowhere.
But, I fail to see how ANY OF THIS applies to YOU since you never play with your gamer peers anyway.
"Your online name is an expression of your personality, a representation of yourself."
Your NWR Display Name isn't even guaranteed to be the same as the username you logged in with. Like email addresses and permanent tags, someone could've signed up with the name you wanted before you got a chance to. Gee, thanks for the opportunity to express myself, I need to add silly numbers or symbols to differentiate myself cuz someone 'took my name.' Oh wait, does that mean we need TWO names to identify ourselves now?
An account ID no one sees, and a display ID we're free to modify? Isn't 3DS already doing that anyway?