Deuteronomy 4:2 “Ye shall not add unto the word which I command you, neither shall ye diminish ought from it, that ye may keep the commandments of the Lord your God which I command you.”
Proverbs 30
“5 Every word of God is pure: he is a shield unto them that put their trust in him.
6 Add thou not unto his words, lest he reprove thee, and thou be found a liar.”
Revelation 22:18 “For I testify unto every man that heareth the words of the prophecy of this book, If any man shall add unto these things, God shall add unto him the plagues that are written in this book:”
To add teachings that are not in the Bible and require Christians to believe them implies that the Word of God is insufficient, that man knows better than God, which is nonsense.
“Why do you bother with the Bible at all ?”
The Bible is the Word of God and sacred. I just don’t impose any false Protestant doctrines on it.
None of the verses you posted actually name, mention, describe, defend, or even suggest sola scriptura.