Last word on Deal Breaker letters (maybe)

In an interview, the American Presbyterian minister and author Frederick Buechner was asked to comment on Jesus' claim in John 14:6: “I am the way, and the truth, and the life. No one comes to the Father except through me.” His reply was this. “What arrogance, but blind egotism that might seem to be, until you live with it for a while and think about it. What was Jesus' way? He didn't say 'What I say is the way;' he didn't say 'Presbyterianism is the way;' he said' 'I am the way.' My kind of life, pay attention to my kind of life, that is the way.”
Later in the interview, he added: “He didn't say, What I teach, or what people teach about me, or the church or any creedal affirmation that is the truth, but 'I am the truth.' What you see in me, the life, the freedom, the compassion, the love that you see in me, that is what it's all about.”
John wrote, “Dear friends, let us love one another, for love comes from God. Everyone who loves has been born of God and knows God.” 1 John 4:7. According to Jesus there will be sheep who arrive in the kingdom who didn't even know they were on the way. Matt. 25:31-46.
Why on earth is this a deal-breaker for the church?