>>260897
Orthodox and Catholics have more or less the same devotional outlook on Mary. We all revere her as the Mother of God (except for the Nestorians I guess), all holy and immaculate, seek her intercession and protection, etc. The Immaculate Conception is not one of the big issues dividing Catholics and Orthodox. The main reason it is opposed by the Orthodox is because it was defined as a dogma by the pope (Pope Pius IX in the 19th century), so it just became another polemical talking point (to put things in perspective, the 1054 schism was primarily about a disagreement over whether it was permissible for Latin priests to use unleavened bread in the mass). Now, the Orthodox never defined a dogma on the Immaculate Conception before or after the schism, but it's not like the Immaculate Conception was never believe in the Eastern Orthodox Church.
https://www.ewtn.com/library/ANSWERS/IMCONCEP.HTM
Another thing to keep in mind is that Orthodoxy has a lot of problems with modernist theology. For example, you might hear people say that the Orthodox Church doesn't believe in original sin for instance. Then you actually read historical Orthodox writings, and realize that this is all a modernist fiction, but people are fooled because it is modernism masquerading in traditional vestments. It would be like if all Catholics argued that we were not like group X because of <insert position of Hans Kung here>.