Yeah, agree with you. Don't see why anyone would try to see some crazy stuff when there are so simple explanations.
At the most we could talk about humans "rewriting history", if we take the example of mandela dying in prison it's very possible that people remember that 'correctly' because they've been told so in one way or another.
Or on a larger scale we celebrate people that were essentially mass murderes because they were on the winning side.
Point being I think you can change the past by active and passive manipulation. Our main source of knowledge of what happened a 100 years ago is usually something written down by someone who most likely was fairly biased...
RE: Is Our Past Been Edited? - Explaining The Mandela Effect