I am sorry but that reply was not to the point and was more a political polemic than a response. Protestants study the Bible for their take on theology and their interpretation of what is “Scriptural/dogmatic”. “Scripture Alone” was their response to what they viewed as an institutional (meaning political) response to what scripture said. As I am sure we all know that there was great misuse during the dark/middle ages of the institution of the church. Protestants wanting to please God and not man tried to find something that gave them firm ground to argue against what they viewed as wrong.
2Tim 3:16 is a strong argument for scripture being infallible:
(here are a number of translation so that you can view all the possibilities and in Latin and Greek for those that can read it. The numbers respond to a Strong Numbers a Greek exegetic.
(ASV) Every scripture inspired of God is also profitable for teaching, for reproof, for correction, for instruction which is in righteousness.
(ESV) All Scripture is breathed out by God and profitable for teaching, for reproof, for correction, and for training in righteousness,
(GNT-BYZ+) πασαG3956 A-NSF γραφηG1124 N-NSF θεοπνευστοςG2315 A-NSF καιG2532 CONJ ωφελιμοςG5624 A-NSM προςG4314 PREP διδασκαλιανG1319 N-ASF προςG4314 PREP ελεγχονG1650 N-ASM προςG4314 PREP επανορθωσινG1882 N-ASF προςG4314 PREP παιδειανG3809 N-ASF τηνG3588 T-ASF ενG1722 PREP δικαιοσυνηG1343 N-DSF
(GNT-TR+) πασαG3956 A-NSF γραφηG1124 N-NSF θεοπνευστοςG2315 A-NSF καιG2532 CONJ ωφελιμοςG5624 A-NSM προςG4314 PREP διδασκαλιανG1319 N-ASF προςG4314 PREP ελεγχονG1650 N-ASM προςG4314 PREP επανορθωσινG1882 N-ASF προςG4314 PREP παιδειανG3809 N-ASF τηνG3588 T-ASF ενG1722 PREP δικαιοσυνηG1343 N-DSF
(ISV) All Scripture is God-breathed and is useful for teaching, for reproof, for correction, and for training in righteousness,
(Murdock) All scripture that was written by the Spirit, is profitable for instruction, and for confutation, and for correction, and for erudition in righteousness;
(NASB+) R1AllG3956 ScriptureG1124 is N1inspiredG2315 by GodG2315 and profitableG5624 for teachingG1319, for reproofG1649a, for correctionG1882, for N2trainingG3809 in righteousnessG1343;
(NET.) Every scripture is inspired by God and useful for teaching, for reproof, for correction, and for training in righteousness,
(NIV) All Scripture is God-breathed and is useful for teaching, rebuking, correcting and training in righteousness,
(Vulgate) omnis scriptura divinitus inspirata et utilis ad docendum ad arguendum ad corrigendum ad erudiendum in iustitia
There are other arguments but this is possibly the strongest from their point of view.
Now to the rest of your questions. Protestants have tradition same as the Roman Church. The difference is the importance or weight - theologians would argue the positional relation of tradition. Let me explain it this way. To the protestant theologian scripture is the only INFALLIBLE source. So in matters of conflict in scripture you must use scripture to interpret scripture. That is your explanation in matters of dogma should not contradict scripture in any way. Tradition therefore is subject or submissive to scripture.
The Roman tradition is seen as ON PAR with scripture - that is the interpretations of those in authority are said to be so closely guided by the Holy Spirit that they cannot make a mistake in matters of Faith and Morals.
The conflict arises then, when are they speaking in Faith and morals, and when they are not. Some, like Francis of Assisi and others would argue, that to often the Church has intermingled the political with the theological. Or to put it another way often those in authority are seen as following mammon rather than Christ.
Now let me be clear, I am not saying that this is the case all or even most of the time but it has happened enough to damage the credibility of the Church in the eyes of some.
Have a God Filled day…I hope this answers your question.