Firstly: The Plato quote is fake - It was crafted by a student, Kenneth John Freeman, for his Cambridge dissertation published in 1907.

Secondly: Hesiod was right, his culture no longer exists. ;-)

Thirdly: Yep, that quote is fake too. https://quoteinvestigator.com/2012/10/22/world-end/

Can't find any sources on that fourth one, but I suggest that the British Medical Journal might want to update their article.