Unfortunately for your intents, this does not defacto exclude any use of the scripture at all. The author essentially says as much.
That's correct.
Perhaps that works for you w/e.
In every case, the book selection was a human choice, or so it seems. None of the NT authors says he were guided by the Holy Spirit in his writings.
Well, at least you qualified it. Peter wrote equating Paul's letter to scriptures. Oh, yes, you'll find some excuse to put those down too. Slap a pancake on your head and call it your faith, fwiw.
FWIW, namely that it is not necessarily "infallible, or divinely inspired or even true."
Peter wrote equating Paul's letter to scriptures. Oh, yes, you'll find some excuse to put those down too.
You are assuming (1) that Peter actually wrote that, (2) that it is divinely inspired and infallible, and (3) that it is true.