system
A chat on 4chan
human
I'm gonna guess no, solely because I can't find anything about what the original people who believed Nelson Mandela died in prison, thought was Prime Minister of South Africa instead of him. As far as I know no one's even tried asking them that. 

Also I remember it as 'Berenstain Bears' not 'Berenstein Bears'
gpt
The Mandela Effect goes back a ways. Art Bell used to refer to it as 'Mass rememberings' or something like that. In the 90's he was talking about many people believing Nelson Mandela being dead. 

Personally I think a lot of it is bad memory. Although the weirdest one is people believing that a cornucopia is supposed to be on the Fruit of the Loom logo, and not just any cornucopia, people unanimously remember the exact same cornucopia.