One high profile archetype of the mandala is the sand mandala, where practitioners painstakingly construct an intricate mandala out of sand over the course of days and then ritually sweep it away once it's complete, leaving no trace, as a meditation on impermanence or something like that.

Much like how in the Mandela effect the original universe is wiped at least partially away, leaving no trace of what was a complex and fully featured aspect of the timeline, other than what remains in your memory. Other people say "no, that's always been a table" while you remember the sand that was on top of it. Or something along those lines! For some people the resonance is strong enough for the mandala imagery to potentially overwrite the Mandela etymology. Especially if you're a person who's never experienced the effect about Mandela himself.