You have to realize that from an Orthodox point of view, every Christian country save the Orientals, Nestorians etc was Orthodox. This includes, England, Germany, France, and Spain. In that effect, Orthodox Christianity did remarkably well when it came to evangelism.
After the schism, Orthodox missionaries converted not only Russia but also Georgia but also Serbia, Bulgaria, and others.
After the Fourth Crusade the Roman Empire ceased to be a meaningful geopolitical force, and all of Orthodoxy was swamped by the muslims and steppe peoples. It's great that Russia became a mighty world power in the 1700s, and the fruits of Russian evangelism were Orthodoxy's spread into North America. It is thanks to Russia that Orthodoxy has a meaningful organizational presence in America today.
I think it did pretty well tbh.