I would agree .Angels have no form, no DNA made up of dust and water and therefore no way to multiply. That portion of scriptures is teaching the believing born again Jew,walking by the faith of Christ that was in them informing them not to be unevenly yoked. In that way God protected the spiritual seed of Christ the word of God from being mixed with other nations. They were giants like Goliath that apposed the Jews.
The context you offered below is in respect to men seen, not angels not seen . He had already dealt with the wickedness of angels.
Gen. 6
5Then the LORD saw that the wickedness of
man was great on the earth, and that every intent of the thoughts of
his heart was only evil continually.
6The LORD was sorry that He had made
man on the earth, and He was grieved in His heart.
7The LORD said, "I will blot out
man whom I have created from the face of the land, “from
man to animals” to creeping things and to birds of the sky; for I am sorry that I have made them."
Not from man to angels, not seen.