The alien Anunnaki fable was created and promoted mainly by jewish Immanuel Velikovsky and Zecharia Sitchin.
Both of these authors were Zionists, heavily involved in the project of occupying Palestine. They were promoted and supported by other jewish publications and authors. Their work was not a one man operation!!! Velikovsky had teams working for him. Their lies are convincing lies because a lot of effort have gone into creating them, carefully crafting them and marketing them.
Unfortunately I do not have a translation of this book by Sayyid Al-Qemany Traditions About the Tribe of Israel in which he painstakingly dismantles the lies of Velikovsky. He reaches the conclusions that Velikovsky did not just make a mistake in judgement but that he deliberately lied and misled and that he could only do it if had a team working for him. Sayyid Al-Qemany was an atheist BTW and not a muslim and had nothing against the jews.
I can see how a lot of people here fall for "It's the Aliens/Anunnaki/Reptilians whatever". always taking to heart jewish fables of the torah as if it was proof of real history, not realizing how they are being misled by jewish israelis deliberately.
So, the lore exists and it is relatively known for whatever reason. How is that different from comics superheroes/supervillains or heroes/villains of fantasy books/movies? They are completely fictional too with tiny tie to actual legends and myths.
How do you know, if the only source of any knowledge about Annunaki is a stories written on clay tablets?