Scripture-first response
“Jesus prayed, so He cannot reveal the Father.”
Jesus’ prayers are real acts of His genuine human life before God. The Father dwelt in Him, but the Son was not pretending to be human.
What the objection is claiming
Prayer is taken to require two separate divine persons communicating inside the Godhead.
Hebrews 5:7-8
7 Who in the days of his flesh, when he had offered up prayers and supplications with strong crying and tears unto him that was able to save him from death, and was heard in that he feared; 8 Though he were a Son, yet learned he obedience by the things which he suffered;Open full referenceIn the days of His flesh, Jesus prayed, suffered, and learned obedience as the Son.
How the passages answer it
The incarnation creates a real relationship between the human Son and God. Hebrews places prayer in ‘the days of his flesh,’ and Paul calls the mediator ‘the man Christ Jesus.’ John 14 explains that the Father nevertheless dwells and works in Him. Genuine humanity and full deity belong together.