If there is something to UFO sightings, I agree, but he lost me at Nephilim. People love that word lately, because it has a vague explanation. I tend to agree with this write up: https://www.gotquestions.org/Nephilim.html
Angels and Demons, more like it.. and specifically, the Seraphim and Cherubim. Satan was of that group. It mentions in Ezekiel 1:15-21 that they had a floating wheel, that could see/move in all directions and was like shining beryl or topaz. (Ophanim, from Hebrew)
The hybrid program lacks the lustiness of the Genesis 6 story, but it seems to be pointed in a similar direction.
“8 As for their rims, they were so high they were awesome; and their rims were full of eyes, all around the four of them. 19 When the living creatures went, the wheels went beside them; and when the living creatures were lifted up from the earth, the wheels were lifted up.”
The “eyes” could be lights on the craft. The wheels could be landing gear? The crafts could be some high-tech (UFO) drones. The inter-dimensional aspect could just mean they require the use of wormholes to travel back and forth from our dimension to theirs. I’m a lifelong SciFi fan, so this subject is fascinating (as Spock would say) to me.
I am of the opinion that “Giant” in the OT is comparable to the modern “strongman” or “tyrant” or “warlord”.
They were created by procreation between a temple prostitute who became ceremonially demon possessed and a king, or a king who became ceremonially demon possessed and a woman.
The offspring had both the natural physical gifts of being offspring of royalty as well as the earthly advantages that may come along with demonic possession.
The giants were feared, evil entities who caused pain and havoc to Godly men.