Thoroughly agree. We have this choice- (or rather faith-)related "seedline" clearly stated in many places:They are a different manner of people and the separation will always exist between those who choose YHWH, and those who choose to fight against Him.
I really believe the "seedline" is not exclusively literal, but rather is partly related to choice. But some choices are passed onto (inherited by) posterity.
Some are called sons of God, some sons of Satan, but neither is necessarily because they were physically 'begotten' as such.
Romans 9:6-8: ... For they are not all Israel, which are of Israel: Neither, because they are the seed of Abraham, are they all children: but, In Isaac shall thy seed be called. That is, They which are the children of the flesh, these are not the children of God: but the children of the promise are counted for the seed.
Galatians 3:7: Know ye therefore that they which are of faith, the same are the children of Abraham.
John 8:39-45,47:
They answered and said unto him, Abraham is our father. Jesus saith unto them, If ye were Abraham's children, ye would do the works of Abraham. But now ye seek to kill me, a man that hath told you the truth, which I have heard of God: this did not Abraham. Ye do the deeds of your father. Then said they to him, We be not born of fornication; we have one Father, even God. Jesus said unto them, If God were your Father, ye would love me: for I proceeded forth and came from God; neither came I of myself, but he sent me. Why do ye not understand my speech? even because ye cannot hear my word. Ye are of your father the devil, and the lusts of your father ye will do. ... He that is of God heareth God's words: ye therefore hear them not, because ye are not of God.
It's so unrelated to the physical that we even have talk of people potentially being seed, then becoming not seed, then becoming seed again:
Romans 11:17-23:
And if some of the branches be broken off, and thou, being a wild olive tree, wert graffed in among them, and with them partakest of the root and fatness of the olive tree; Boast not against the branches. ... because of unbelief they were broken off, and thou standest by faith. Be not highminded, but fear: For if God spared not the natural branches, take heed lest he also spare not thee. ... And they also, if they abide not still in unbelief, shall be graffed in: for God is able to graff them in again.