"Scripture preserves God’s truth from drift into all kinds of foolish pagan practices."
Absolutely true. That's why the preservation, collection, translation, publication, interpretation and proclamation of Scripture has always been the vital concern the Church. It's been one of the Church's principle tasks over the past 20 centuries. That's why any of us is able to have a Bible in his hands to this very day. Phenomenal, isn't it?
"It prevents what happens when Scripture is discounted and any leader can make up new traditions - even ones that didn't exist during the first one hundred years of Church history - and you end up with a situation where anything becomes tradition that invalidates the Word of God for the sake of traditions."
Absolutely true once again. This preoccupation we have with Scripture HAS prevented erroneous teachers from making up new traditions which invalidate the Word of God.
If you look at the 21 Ecumenical Councils, for instance, beginning with the Council of Jerusalem as reported in Acts, you will see that these Councils protected the Church by striking down erroneous traditions. Note that many of these heresies were being promoted by dissenting clergy and had hundreds of thousands of enthusiastic followers. But the Church had to battle these wolves-in-shepherds'-clothing and reinforce the unchanged Faith as handed down to us by the Apostles.
Extend this Chart all the way down to the 20th century: the Church has always had to face and combat the roar of dissenting voices, the "Spirit of the Age," the exceedingly popular heresies.
“As evidence consider the state of protestant theology in the US at present (or Europe for that matter ). If you look at raw numbers well over 60% now teach either abortion or same sex marriage are perfectly ok and its growing rapidly.”
Exactly. They have their own conferences every couple of years or every decade or so, not to refute the heresies, but to adopt them. (Who knows what the Episcopalians will come up with next??)
"As evidence consider the state of the Roman Church worldwide, where regardless of what the church teaches, a huge number of members use birth control, get abortions and are perfectly ok with same sex marriage."
This is where you need to take another look, because this is not evidence for your claim, but counter-evidence. Namely, here you're dealing with a Church which still has its pure doctrine -- FOR the truths of Scripture, AGAINT birth control, AGAINST abortions, AGAINST the deconstruction of sex, gender and marriage --- and still has to fight the usual opponents, i.e. dissenting clergy and their millions of enthusiastic supporters.
Today the heresies center, not on the nature of God, but on the nature of Man. The dispute isn't about whether Christ had a human nature, but whether "human nature" even exists.
Find another Church which hasn't given in, hasn't changed its doctrines to accommodate serial polygamy (divorce/remarriage), onanism (contracepted sex), sodomy (perverted sex acts, whether by homosexuals or heterosexuals), infanticide (abortion, even in the so-called "hard cases"). Find me another Church with clear-cut doctrines against human embryo experimentation and manipulation; against alternative reproductive technologies; against euthanasia and the intentional programming of death.
Well?
And I still like you too ;oD