No, but worshipping Mary IS idol worship.
The doctrine of “sola scriptura” is - in fact - a doctrine. And it avoids the question of differing interpretations of scripture by various denominations. Who decides which interpretation is correct? In Catholicism and Orthodoxy, it is the Councils and the Fathers. In Protestantism, every man is his own Pope, hence the multiplicity of denominations.
The last of the Gospels warned about this:
John 21:20-2320 Peter turned and saw that the disciple whom Jesus loved was following them. (This was the one who had leaned back against Jesus at the supper and had said, “Lord, who is going to betray you?”) 21 When Peter saw him, he asked, “Lord, what about him?”
22 Jesus answered, “If I want him to remain alive until I return, what is that to you? You must follow me.” 23 Because of this, the rumor spread among the believers that this disciple would not die. But Jesus did not say that he would not die; he only said, “If I want him to remain alive until I return, what is that to you?”
Sadly, many rumors have spread amoung believers, so much so that they have superceded clear biblical teaching.