Well if there is open communion then I am not sure it is appropriate. But it seems to me to depend on what is meant. If we mean that in a beleagured village somewhere there are Catholics who attend the Orthodox Liturgy because their church has been bombed, and they recieve communion, well I am not sure that is entirely unacceptable.
Our Father, St Severus was clear that obstacles must not be put in the way of the simple lay folk who usually do not understand entirely what the various disputes are about. I think this is, to some extent and in some cases, an applicable principle.
Note that I am using 'some' a lot. I am not suggesting it is a universal principle. If it were a universal principle in the Syrian Orthodox Church then it does strike me as rather problematic. If it does not extend to clerical communion then it is less problematic but still not non-problematic.
On the other hand, His Holiness Pope Shenouda clearly believed that the Catholic Church is Apostolic, and has true sacraments. That being the case then it could be said that communion of laity could perhaps in some cases be allowed if it was clear that those communing held no definite heresy. I would want to wonder whether two Syrian farmers, one an Eastern Rite Catholic and the other an Eastern Rite Orthodox would necessarily have a different substantial faith? Once we demand that all laity pass an exam proving that they are entirely Orthodox in all possible aspects of their faith and practice then that also becomes problematical.
There are issues around some of the present thinking in the Syrian Orthodox Church which are indeed problematic. Especially around primacy. I am not diminishing this. But we also have many problems in our own local Orthodox community. So I am not sure where, in the order of priorities, this particular issue comes. I would be more concerned about the teaching of the Syrian primacy over the other Churches.
I guess I consider that open communion is not appropriate, and that the communion of clergy is particularly inappropriate, but I am less concerned, in the face of many other problems which we all face, if there is a sense of Syrian identity and Christian unity in Syria in the face of the terrible situation that all Christians find themselves in.
When Constantinople was about to fall to the Muslims all of the Christians united in communion in Hagia Sophia. I find myself moved by this, and not to criticism.