That's an interesting point. We can leave aside the Wesleys, who held themselves in the tradition of the Church of England and did not claim a unique theological truth, but more like an approach to Christian practice.
However, Martin Luther, John Calvin, and John Knox (and Arminius and Melancthon and other "losers" in the Reformation struggle) were sufficiently persuaded of their absolute Truthiness that they established states in which disagreement was punished with death. The way I see it, that's as near a claim of infallibility as makes no difference.
Indeed the era was full of bloodshed, which I will clearly note is not following the Voice of The Good Shepherd. Be careful, however, Rome had its hands immersed in bloodshed as well. That is why I stated to one poster we should throw all the theologians out with the bath water and be like the believers in Berea who searched the Scriptures to see what Paul was telling them was true.
So call me a 'bad' Reformation 'soldier' and former Roman Catholic. I will not fall on my sword for Luther, Calvin, Knox et al nor any Pope who have blood on their hands. I will fall on my sword for The Good Shepherd for I hear His Voice. God the Father at the Transfiguration told the disciples to Listen to Jesus. We can't go wrong there.
If you would ask me what theologians best express my beliefs, I would say #1 Jesus Christ and #2 His apostles. Out of all the apostles, the one who received a direct commission to bring the Gospel to the Gentiles was St Paul of Tarsus. With Paul's background as a Pharisee, he was an expert on Hewbrew Scriptures specifically The Law. So out of the apostles Paul was the most qualified to encapsulate the doctrine of Salvation. He did so in his epistles and the crowning achievement IMO is Romans. It is all there.
So we have the direct Words of Jesus Christ (what we call these days the "red letters) in the Gospels; we have the Work of Christ accounted; We have His death, burial and Resurrection; We have Jesus giving the Great Commission to all His disciples and apostles; we have in Acts the Gospel preached in action by the apostles; and finally we have the written Holy Spirit inspired writings of the apostles in the epistles. All of the above is sufficient for us for the knowledge of salvation and godly living for Christ.