"Mandela Effect" was coined by a paranormal "consultant" named Fiona Broome. She remembers Nelson Mandela as having died in the '80s...hence the coinage. It seems to center around whether or not Stan and Jan Berenstain actually knew their own last name. It's funny. I read many of those books to our son when he was younger, and we have some (not many, because I didn't like how the father was always the dumb one...). I never REMEMBERED it being spelled -ein - I ASSUMED that was the spelling until I went to work at the library and had to page (shelve) them. No alternate universe explanation for me. =D Nor Mandela Effect. Simply not paying attention to the author's name/series title, assuming the -ein spelling, explains it. For me as well as most likely anyone else that "misremembers" the spelling.
And then there are the Christians who claim it's all an anti-christ conspiracy (false memories planted to make folks THINK Mandela died and it actually USED to be Berenstein, etc., etc....sigh...
I agree with NN - applying this idea to scripture is simply because people don't want to take the time to learn what God's Word actually says.