“Ancient astronaut theorists suggest...”
Heiser's work is all grounded in the Bible and in Sumeria/Mesopotamian literature...and it supports what was thought to be true by many authoritative Biblical scholars at the time of the Birth of Christ and before.
Ha! Not quite.
This book suggests that mankind has risen to great technological heights in the far distant past, only to be wiped out by extinction level cataclysms, over and over again.
That actually makes sense to me, as we have solid evidence for such events in the geologic record. For me, it goes a long way towards explaining many of the anomalous artifacts that still stand today.