Is the current obsession with "nephilim" possibly leading to some doctrines being impacted?

I've heard and read many, recently, claim that the judgment on the world in Noah's day was because all men,

except for Noah and his wife, had angel blood, or angel DNA, from the nephilim half-breeds.

Also, they went on to say that the reason that Israel was to kill every man, woman, and child in Canaan,

was for the same reason, that the Canaanites also had angel blood, or angel DNA,

from the post diluvian nephilim half-breeds.

But wouldn't that be teaching that the judgment of the LORD was because of genetics,

rather than because of sin?

What about the reason for death itself coming into the world?

Romans 5:12 Wherefore, as by one man sin entered into the world, and death by sin; and so death passed upon all men, for that all have sinned:

Or what about the children of disobedience, rather than the children of nephilim?

Colossians 3:6 For which things’ sake the wrath of God cometh on the children of disobedience:

A judgment based on genetics would not require the cross, would it?

Wouldn't it then be to simply keep one's bloodline clean?

Also, didn't the Nazi's have a "genetic reason" for killing people in the concentration camps?

I've recently heard some people teaching that the post diluvian nephilim came from Ham's wife.

That she supposedly had fallen angel blood, angel DNA, from the nephilim, and that she passed it on to Canaan.

That this was the reason that all of Canaan was cursed and had to be destroyed.

However, were not both Tamar and Rahab from Canaanite background?

Were they not both in the lineage of the Messiah?

Even though Joseph was only Jesus' stepfather, Mary was his actual mother, though.

Wasn't Mary also of the line of David through Nathan, another son of David and Bathsheba?

So if Ham's wife is taught to have had fallen angel blood, fallen angel DNA, from the nephilim,

wouldn't that then blasphemously imply that it was passed down to flesh of Jesus?

So, is the current obsession with "nephilim" possibly leading to some doctrines being impacted?