Understood and I agree that there is a fundamental and personal decision that leads one in a given direction.
However - there is (IMHO) also a very basic and fundamental principle in Protestantism that elevates this personal decision over the Biblical principle (and instruction from Christ) to submit to the authority of His Church.
This principle stems, I believe, from the very foundation of Protestantism. The Protestant reformation is founded on the principle of the rejection of ekklesial authority. The denial of the unified authority of the Church. I don’t believe this is quite what the original reformers had in mind, but this is what came out of it.
If Luther need not submit to Rome, then Zwingli need not submit to either Rome or Luther, and Calvin can likewise go his own way etc…Each believing the others are wrong and none of them calling for a council (ala Acts 15) to resolve the differences between them. This principle has, after 500 years, resulted in so many different teachings that a person can find a “church” to fit pretty much anything he/she chooses to believe without the need for any submission to authority whatsoever.
It is my belief, and my experience, that this fundamental principle (AKA Tradition is so deeply embedded in Protestantism that. like Sola Scriptura, most protestant Christians never consider or - indeed - ever even recognize it.
Peace
James