There are way too many both long forgotten and completely destroyed past civilizations of old to discount the existence of the Anunnaki at the least.
Somebody or one thing was creating an entire slew of “overnight” civilizations for many 1000’s of years everywhere in the Earth, even in Antarctica earlier than it froze over and have become the Antarctica we all know in the present day.
Somebody or one thing not only created those “overnight” civilizations but outright destroyed them so completely that there’s nary any physical proof of most of them at present.
A few of these ancient civilizations are solely known to have existed by totaled ruined ruins and them being still majorly hot to this very day. By “hot” I mean radioactive.
There are at least three major former Indian cities in northern India that got nuked out of existence. They are still hot to this very day due to how overwhelmingly powerful the nuclear weapons used back then.