Originally Posted by American Maid
But the whole premise is that these Asgardians really have been to Earth, and that was the foundation for these stories. Another goof, from Thor1, is that Thor and Loki are supposed to have been born in the mid-900's CE. But the Norse myths go back to the first century CE at least. So how could the Midgardians know about Thor (and his cohort) before Thor was born? Another oops.
Regarding that, I have wondered before if what will be revealed is previous incarnations of Thor etc have been to Earth, (due to the whole Ragnarok thing), setting up the mythology in the MCU, but not necessarily THESE versions (or not so much). Based on Thor's behavior, if he's been to Earth it probably wasn't recently, due to his lack of savvy. But Loki on the other hand, I could see having been to Earth MANY times in recent past.