“...if these people really believed they’d ever have to give an accounting.”
That is precisely what the Christian Walk is all about. It is the accounting and repenting of our sins as He reveals them.
Not so fast there, FRiend. According to the Bible, we will ALL give an accounting, and not just for sins. Furthermore, how do you think he would "reveal" deeply flawed, but popular doctrines in his own Church?
The problem with 1 Thess 5:21 is Paul didn't add "not just the things you don't like" to "test all things, hold fast that which is good."
If your "Salvation Experience" was something out of your own imagination, how could someone prove that to you?