It is obvious if you think about it. Selfish people ruin everything and need to be removed. We all have free will. So we should fear God.
Then we couldn't justly be punished. And wouldn't need an atonement.
to will is present with me, but how to perform what is good I do not find.
The bible says to love God with all of your mind, not more than all of it. If someone can't figure out how to obey God then they are not transgressing His law. "with all of your strength" not more than all of it. If it is a matter of ability then only the ability we have is required (justice).
That passage is describing a self-inflicted inner conflict. Not a literal glitch in free will. It's describing a convicted legalist who is confessing to Ray Comfort. It's saying,
"In my mind I naturally want to obey God's law but, since my bottom line is that I disobey the truth by being unnaturally selfish, I can't." It's a personification of sin as a separate agent intended to vindicate the law, not intended to vindicate the person who is being figuratively split in two. Original sin is you. Sad but true.
Then He wouldn't punish us for our inability. And He wouldn't require the suffering and death of Jesus in order to accept us. He would just care and admit we couldn't help it. If your child gets a math problem wrong you don't need to kill anyone. They couldn't help it.
So it is not that we are born into a state of unrighteousness but that we are not born righteous.
You said, "in a state of unrighteousness and all unrighteousness is sin". Is the state we are born in a sin? If so, then it is a "sin" we are not the cause of. Are we the cause of the state we are born in? No one can be morally guilty for something they are not the cause of.
Has it never occurred to you that this is why grace.
I used to think Jesus must have had to die because of human inability. Now I know Jesus died because of the misuse of human ability. For His enemies not invalids. Criminals not cripples. Rebels not victims.
God does not view sin the way liberals view crime.