So who "relaxed" the contraception teaching within the Orthodox? Did the people "vote" on this? Was their a Council that refuted it? What happened some 75 years ago?
Try not to be thrown by "papal supremacy". It gives the Pope the POWER to do "x" and "y", but in practice, he rarely uses it, choosing to NOT lording it over others. Techinically, the Pope could disband schools that teach incorrect practices, bar theologians who teach incorrectly, chastise local churches for improper liturgical practice, and so forth. SOMEONE should have this power - IF the Church IS ONE! But, in reality, how often do you see the Pope practicing these "powers"? Hardly ever. Perhaps most would agree that he SHOULD DO MORE!
Regards
Certain Bishops in Certain Jurisdictions, same as within the Catholic church relaxed the teaching. (I think I posted a link to an exhaustive look at this).
The orthodox objection to the papal supremacy is not with regard to how often he uses it, it is with regard to the fact they find it heretical.