Not sure I totally get your point.
The Scriptures nor Enoch record
WHAT PERCENTAGE of the 1/3 angels that fell with satan
did the earth bit of messing around with human women.
Only THEIR bodies were trashed during the flood.
The Prince and Power of the Air obviously still has plenty which still have their fallen-angel bodies.
Quix,
A cursory read of what he wrote suggests to me he’s referring to the understanding of the “sons of God” as the line of Seth who were faithful and the “daughters of men” as the line of Cain who were not.