This is the true God, and eternal life, is stating that the reality of God, His truth and eternal life are accessed by the perfect mirror, Jesus, who reflects all the qualities of God. Who in this age was the only mediator between humans and God.
This is not saying Jesus is literally God, because this would be nonsensical. Jesus made no claim that He was God.
That God the prefect Creator should enter the relative imperfection of physical reality is a strange imagining of God. Jesus was a path to the truth of God, to the true God, and to eternal life. He was not God Himself. Otherwise we have to imagine a God that needs to eat, defecate, becomes soiled and is eventually murdered by His own Created creatures.
I imagine that people don't know any better because suggesting Jesus is literally God, if thought through properly would have to be blasphemy against the perfect, eternal nature of God, who is transcendent, not subject to humans.
Son of God denotes the closeness of the relationship, the obedience a son has to the father, the son promoting the Will of the father and not his own, etc, it does not mean literal Sonship.