St. Stymeon the New Theologian is highly revered and his works are closely studied in the Eastern/Byzantine Catholic tradition(s). I'm pretty sure his feast day is also celebrated in some of the Byzantine Catholic Churches, although I don't know the date of his feast. The late Fr. George Maloney, S.J., a Russian Catholic priest, was heavily influenced by the writings of St. Symeon.
While Rome may have some hesitations about this great saint, the Catholic East certainly does not.