To be extremely futuristic and extremely retro at the same time, depending on which century everything gets nuked. Perhaps that Mandela Effect is the result of all the times we nuked the planet, every single one of Schrödinger's cats(us) was incinerated instantaneously and continued to exist in a slightly different parallel universe than the previous one we collectively went extinct in. https://simple.wikipedia.org/wiki/Quantum_immortality