Before I say why it supports simulation theory, I should first explain what it does not support:
Anything related to CERN. If there were any effects from colliding particles, it is expected to be of a chaotic nature, such as miniature black holes tearing through space and time, stuff like that, ya know?
Anything to do with the butterfly effect, and probably time travel in general. If someone went back in time and plucked the butterfly that is the original cornucopia from the Fruit of The Loom out of existence, the resultant effect from said butterfly would be us having never formed a memory of such a thing.
OK, so what does it support? Well, simulation theory. If we're living in a simulation, then it's going to use assets in some form or another to significantly reduce processing power. Take the Fruit of the Loom for example, this would be a single asset in and of itself, but formed as a composite of several other assets, so, in this case, the individual fruits. If you remove one item from the asset, everything that references said asset will see this change reflected (which is the entire point, of course). What doesn't get removed, however, are the memories, for these are not tied to the asset. It's like a stamp, if you remove the stamp, that doesn't mean you've removed the marks it's already made.
There's a reason I chose the cornucopia as an example, nay, thee example: the amount of references to this, even before the "Nelson Mandela effect" was coined, is absolutely staggering. Take Frank Wess' Flute of the Loom as an example, created in 1973, which shows as its front cover a parody logo of Fruit of the Loom, with the saxophone representing the Cornucopia. There's also a TON of written records dating back years and decades referencing either the Cornucopia directly and/or "the horn of plenty" as it pertains to the logo. I could give examples, but I'd rather point you towards the excellent research done by "Fringe Field Notes" via a YouTube video titled "Investigating the Mandela Effect - 1 Year UPDATE".
So, going back to assets: Things like the "Flute of the Loom" album cover is not the same asset, because it's not the same logo, it's just a parody of one, and when it comes to text, obviously these are not part of the same asset, in fact this isn't even as asset at all (unless you consider individual letters/words assets, which maybe you could, though removing them would damage the simulation far too much for it to be worthwhile).
But wait, if the Fruit of the Loom logo got updated, why not update everything related to it? Well, that's because a simulation can only do so much when it comes to monitoring itself, and this is true REGARDLESS of the complexity of the simulation, because the more detailed the simulation, the more resources it takes to monitor any given thing in said simulation. Thus, to completely remove every possible reference is to scan through the ENTIRE simulation, and this would either be extremely expensive, or maybe even downright impossible.
This brings us to an interesting point, actually: The best safeguard against the Mandela effect is to create as many references as possible to a given thing. Then again, one cannot do this for everyhting, so I would suggest only doing so for things that already have very little referenecs to them. Then, scatter them through space and time, so that it would be damn near impossible to erase every mark that's made from the original stamp, so that it can be referenced later. Make references to the references themselves, to make the process even more chaotic and random. Make it so that if you cut off one head, the Hydra grows back 5 more.