Elon has gone on record saying he's a huge sci-fi fan, and has mentioned Iain M Banks in particular who writes a lot of posthuman and transhuman characters. He's literally pulling his ideas directly from fiction.
Nothing wrong with that, being visionary was the domain of writers and artists through all ages, Jules Verne springs to mind as someone who inspired a lot of inventors of modern things. Missing the point completely and finding ways to abuse those visions was the domain of the bourgeoisie, through all the same ages, up to and including today.