Trinitarianism doesn’t deny that a shift in theology occurred. It asserts that such a transition took place. It documents that it happened. This is simple and straightforward church history. Non-trinitarians should know it, should accept it; not dispute it. The same, I’m calling for, goes for trinitarians.
I would contribute the following on behalf of outstanding trinitarian scholarship.
”Jesus, in his teaching, his prophetic actions, and in the obedience which led to his death, was acting as God’s agent and representative on earth. It was as if, when he spoke and acted, God himself was present. In Luke’s phrase, ‘God was with him’; in Paul’s, ‘God was in Christ’. That this was so had been demonstrated by the resurrection, after which Jesus had necessarily been given the highest place, under God, which could be awarded to any living being. Christians could now confidently join in the worship and praise due to the one who had been given (again under God) a name which is above every name, and through whom the Holy Spirit was now active among those who acknowledged his lordship. It was as far as one could possibly go (these Christians felt) in ascribing unique dignity to Jesus consistently with respecting the constraint of monotheism. In later times the church, no longer perceiving the power and decisiveness of the agent-son-representative model, and having among its members men used to a more philosophical analysis, felt it necessary to go further in the direction of metaphysical identity between Jesus and his heavenly father: released from the constraint of Jewish monotheism, gentile Christians began to to think of Jesus as also, in some sense God.”
(A.E. Harvey, Jesus and the Constraints of History, p. 173)
Bold is mine.
The trinitarian recognizes and acknowledges my place - the place of Jewish monotheism - on the Church timeline without attacking or undermining his historical orthodox trinitarianism. He is giving us basic church / Christian history.