Whom did the Orthodox Christians of Eastern Europe sympathize with in the 16th century – Catholics or Protestants?

Since the time of Gregory VII, the Orthodox Church considers Catholics to be its enemies, therefore, in the struggle between Catholics and Protestants in the 16th century, it did not sympathize with either side, but it treated the oppressed Protestants better.

Remember: The process of learning a person lasts a lifetime. The value of the same knowledge for different people may be different, it is determined by their individual characteristics and needs. Therefore, knowledge is always needed at any age and position.