If this is it in scripture then that is quite poor for convincing anyone. And if there are a few more suspects lying about then they also add to naught as all of them as well as Phil 2:5-11 fortunately are not about Jesus pre-existing at all.
I didn't claim I had done an exhaustive search for all verses that implied Jesus' pre-existence. I just quoted a few verses.
A more obvious verse is Colossians 1:16 (WEB):
(16) For by him all things were created, in the heavens and on the earth, things visible and things invisible, whether thrones or dominions or principalities or powers; all things have been created through him, and for him.
Lots of earthly and heavenly things existed (like the planet earth!) many thousands of years before Jesus was sent by God to live (and die) as a man on the earth. If all those things were created by Jesus, then it is obvoius that Jesus must have existed before he was born in Bethlehem as a human baby, and he could not have existed as a man because a man could not create the universe, heaven and all living beings, both spirit beings and animal.
As the incarnate believer would plead- cannot you see, He emptied himself, oh wow....look what he did, he was divine and now volunteered to stop being god and become just a man. What a piece of fantasy and trash. Of course is a mantra and must be said over and over again to comply and obey and worship the triune god model they idolize.
It's fundamental to how God is saving mankind. In order to redeem Adam (buy back his right to life), and all Adam's posterity, somebody had to pay the penalty for Adam. The penalty was death. God is immortal so He could not volunteer to be the redeemer; all men were decendants of Adam from after the penalty had been applied (Adam's nature became corrupted and slowly started to decay into eventual death) and therefore had inherited his imperfect, corrupted human nature, so no man could provide an equal price - the death of a
perfect man. So God chose that a spirit being (pre-existing) should undergo a change of nature to become human, which meant that the baby boy had to have been born from a virgin so that he did not inherit the corrupted human nature from Adam. God chose His Son Jesus for this role, not one of the angels, so that Jesus would have preeminence in everything over all God's creation (Colossians 1:18).
God didn't just create another perfect man, as you seem to believe. The first perfect man had no knowledge or experience, and he only lasted a very short time before he sinned. Another perfect man would likely also fail to live a perfect life. But Jesus, God's only begotten Son, had all knowledge of how to live a perfect life, and why. And he did live a perfect live, without any sins - Hebrews 4:15 (WEB):
(15) For we don’t have a high priest who can’t be touched with the feeling of our infirmities, but one who has been in all points tempted like we are, yet without sin.
Therefore God was justified in restoring Jesus to life again, because he had not sinned. And Jesus having paid the penalty for sin for Adam and his descendants means that God is also justified in resurrecting all humans to life again. Jesus prayed to God that He would restore him to how he was before God changed his nature from spirit being to human being - John 17:5 (WEB):
(5) Now, Father, glorify me with your own self with the glory which I had with you before the world existed.
but God rewarded Jesus with a greater glory, and gave him an immortal nature (previously he was mortal, which is why he was able to die in order to redeem mankind), and gave Jesus all authority in heaven and on the earth (although still subject to God, of course). This is why the "triune god model" cannot be correct. Jesus is the only begotten son of God, and therefore an heir of God, and Christians are also heirs of God:
Romans 8:16 (WEB):
(16) The Spirit himself testifies with our spirit that we are children of God;
(17) and if children, then heirs; heirs of God, and joint heirs with Christ; if indeed we suffer with him, that we may also be glorified with him.
Jesus is a son/child of God, and so are Christians. None of them are God, or part of God. The good news continues - Romans 8:18-32 (WEB):
(18) For I consider that the sufferings of this present time are not worthy to be compared with the glory which will be revealed toward us.
(19) For the creation waits with eager expectation for the children of God to be revealed.
(20) For the creation was subjected to vanity, not of its own will, but because of him who subjected it, in hope
(21) that the creation itself also will be delivered from the bondage of decay into the liberty of the glory of the children of God.
(22) For we know that the whole creation groans and travails in pain together until now.
(23) Not only so, but ourselves also, who have the first fruits of the Spirit, even we ourselves groan within ourselves, waiting for adoption, the redemption of our body.
(24) For we were saved in hope, but hope that is seen is not hope. For who hopes for that which he sees?
(25) But if we hope for that which we don’t see, we wait for it with patience.
(26) In the same way, the Spirit also helps our weaknesses, for we don’t know how to pray as we ought. But the Spirit himself makes intercession for us with groanings which can’t be uttered.
(27) He who searches the hearts knows what is on the Spirit’s mind, because he makes intercession for the saints according to God.
(28) We know that all things work together for good for those who love God, to those who are called according to his purpose.
(29) For whom he foreknew, he also predestined to be conformed to the image of his Son, that he might be the firstborn among many brothers.
(30) Whom he predestined, those he also called. Whom he called, those he also justified. Whom he justified, those he also glorified.
(31) What then shall we say about these things? If God is for us, who can be against us?
(32) He who didn’t spare his own Son, but delivered him up for us all, how would he not also with him freely give us all things?