I've researched this for years. My two bits is this. While it is conceivable an ancient, now vanished reptilian race once warred with and conquered the Children of Men, they are long gone and left a genetic legacy as lizard brained sociopaths/psychopaths who now function as our ruling elite.
(For an exciting version of how the Gods cast off their yolk look up the tale of the Tuathat De Danaan defeating the Fomori, Indra defeating Vritra, Ra beating the serpentine Apophis, your own YHWH breaking the "sea monster", S. Michael slaying the dragon...all different traditions, one story. A race of reptilians beings came up from the sea, conquered us and with the help of the Gods, who perhaps gave us their technology, we vanquished them. But did they really leave is the question?)