It's something they've been somewhat reluctant to do since defining it to any degree would mean limiting it at least somewhat. This sub-forum is meant to be as big a tent as possible where, say, Anglicans (of whatever persuasion) and Orthodox can discuss things together and then maybe a Lutheran can dive in and give his perspective too.
My view loosely is that if your congregation has any regard for tradition, odds are you'll fit in around here.
There's a lot about ACNA that isn't all that clear. And I speak here as a former participant at an ACNA parish which I loved dearly. That parish is pretty solid but ACNA as a body has challenges, to be polite.
Since I have your ear, as it were, you mentioned Anglo-Papists in the OP. I keep hearing that such people do exist in a general sense but I've never actually met or even heard of such a person.
That makes two of us, actually. The success of the TT sub-forum has always been a big surprise to me, especially considering how relatively inactive the old Apostolic Churches sub-forum usually was.
A lot of traditional Christians believe in unity... and reunification (at least on some level). Ecumenism is therefore not only inevitable but highly desirable. Effectuating that is, of course, the challenge but the intent is apparent in a great many cases.