For what it's worth, our priests here in ABQ won't commune Chalcedonians of any stripe, though Stavro has commented that this seems like a minority opinion. It seems, from the point of view of someone new to all of this stuff, that perhaps the Syriacs and Armenians are relatively more open to ecumenism and eventual intercommunion with Catholics than either the Copts or the Ethiopians. Maybe I'm just surrounded by extremists, I don't know.
But it might also have to do with the relative proliferation of non-Orthodox churches in their historical homelands, combined with the realities of having large diasporas in many non-Orthodox lands. I mean, I'm pretty sure that Catholics outnumber Orthodox in Iraq, and the Syriac Indians have been a minority within a minority for centuries now. It does not help matters that the Rome-affiliated churches that are made from former sections of these churches are encouraged to look and behave exactly like their mother churches. And then there's Protestantism, further watering everything down to a kind of "I'm okay, You're okay" pietism. Even the Tewahedo have experienced massive losses due to Protestantism, but those are recent (~ since the end of the Derg), so their attitude is still more defensive, rather than the Armenians (for instance), who have had to cope with the reality of a huge diaspora in primarily non-Orthodox countries for a long time now, which I have to imagine has an effect on how they relate to their faith vis-a-vis that of others.
I dunno...maybe that's all hogwash, I'm just trying to come up with some kind of charitable explanation for something I don't like.