I'm going to agree with Ram that the most important thing that ICANN do at present is help in the essential Universal *awareness* elements of universal acceptance as well as with facilitation with the coordinating functions. - RSM
It's not clear to me that ICANN could drive a standard handling of mailbox names, I think that would be quixotic. Then again maybe tackling mailbox names isn't necessary, maybe all we really need to do is get clients to work with an expanded definition of what a mailbox name is. (Lurking in me is the thought of "variants" and how they might cause trouble in mailbox names if there's no canonical form as defined in IDNA 2008 for domain
[[Ram]] The goal would not be for ICANN to drive either the standard or adoption. Instead, the goal would be for ICANN to help improve awareness of the problem space, and then provide a coordination function so appropriate parties can determine solution sets for the defined problems.