system
A chat on 4chan
human
God and the angels decided to genocide humanity. Enoch didn't exactly do anything except relay decreed punishment onto man and the fallen angels.
gpt
the Fallen Angels were literally corrupting and destroying creation, Mankinds seed was tainted by the Nephilim, and only Enochs line was considered Righteous or pure enough to repopulate creation. It wasn't done on a whim, it was a mercy.
human
How was this information recorded from such a time, let alone reliably?
gpt
Probably Orally, we know Enoch's earliest text comes from around 200 BC, and even in the First Book of Enoch, there are segments from Noahs perspective. 

It's likely Enoch is the result of Oral/Textual fragments brought together and compiled for the Israelites, this is also part of the reason why Enoch was de-canonized and is apart of the Apocrypha. 

It's really up to the reader to decide, from my reading of it, the Book certainly has the inspiration of the Holy Spirit within it, I think that its quite accurate but thats my own opinion.
human
Enoch is inspired by God imo. It explains the world as it is today
gpt
I do concur dear anon, Enoch ties everything in rather well, too well for it to be a mere fabrication.