This is hogwash wrapped up in poppycock.
Of course the bible is important. After all, we would not have any idea who Jesus Christ is if we didn't have scripture. How many people, for example, do you know who heard about Jesus directly from the Holy Spirit? How many learned about him from nature? How many learned about him from the world?
On the other hand, how many learned about Jesus Christ either on their own through the bible or from someone else teaching them from the bible? My guess is a conservative 100%. In God's wisdom, we are able to deduce something of his existence and goodness through nature. However, it is through his written word that we learn critical specifics about exactly who he is, what he has accomplished, and what he expects of us. Psalm 19 spells out for us the difference between God's general revelation (19:1-6) and special revelation (19:7-11):
1 The heavens declare the glory of God,
and the sky above proclaims his handiwork.
2 Day to day pours out speech,
and night to night reveals knowledge.
3 There is no speech, nor are there words,
whose voice is not heard.
4 Their voice goes out through all the earth,
and their words to the end of the world.
In them he has set a tent for the sun,
5 which comes out like a bridegroom leaving his chamber,
and, like a strong man, runs its course with joy.
6 Its rising is from the end of the heavens,
and its circuit to the end of them,
and there is nothing hidden from its heat.
7 The law of the Lord is perfect,
reviving the soul;
the testimony of the Lord is sure,
making wise the simple;
8 the precepts of the Lord are right,
rejoicing the heart;
the commandment of the Lord is pure,
enlightening the eyes;
9 the fear of the Lord is clean,
the rules of the Lord are true,
and righteous altogether.
10 More to be desired are they than gold,
even much fine gold;
sweeter also than honey
and drippings of the honeycomb.
11 Moreover, by them is your servant warned;
in keeping them there is great reward.
The Holy Spirit is faithful to illuminate our minds to assist us in understanding scripture correctly. The Spirit also regenerates our hearts to enable us to repent and believe. Additionally, the Spirit leads us day-by-day to live according to God the Father's desires. However, the Holy Spirit is generally not in the business of explaining to people God's plan of redemption apart from the bible.
The fact is that without the bible the vast majority of us (probably somewhere between 99 and 100% of us) would have no clue about Jesus Christ. And if we didn't know the Lord, we would have no opportunity for salvation. It is truly that simple.
Therefore, whether some Christians like it or not, the bible is absolutely essential to the Christian life.