Mmmmmrph. I won’t disagree with the idea that Sam deserves protagonist classification, but the idea that Frodo doesn’t have agency is a stretch. At several points during the story arc he faced decisions that would have altered the outcome. He decided to be the ring bearer. He decided to go to Mordor. He decided to abandon the fellowship and go alone. He decided not to put the ring on, at least most of the time.

Perhaps when he made the first really fateful decision at the Council of Elrond, he didn’t fully appreciate the significance. But if that decision wasn’t agency, I don’t know what would be.

Although I will say Sam probably made the more difficult choice, being less suited to the journey by nature and probably fearing it much more.