The Bible's poetry is lost in the modernized editions. This might not seem like a big deal to the average reader, but consider why the King James Bible is an essential pillar in the foundation of English literature. The specific phrasing matters, because that language contains the literary allusions, sayings, and allegories that have given the Bible such a distinguished place in our literary tradition. Many, maybe even most, of the great books in the Western canon owe a profound debt to the King James Bible. And so does Western culture broadly. Hundreds of our common idioms, like "a cross to bear," "a man after his own heart," "pearls before swine," "a two-edged sword," and "a wolf in sheep's clothing," are derived directly from the KJV.
The modernized versions are pablum, as worthless as classic books rewritten for children. Just as the point of reading a classic is far more than simply to find out what happens, the King James Bible is worth reading for the range of effects produced by the exquisitely wrought language, the richness of imagery and metaphor.