What aligments would future calamities even have had?

[Cleretic]

I honestly have no idea what fan theories are out there, its not something I follow. I get all my info from the game and live letters but I don't keep clips saved on my computer.

Then can you provide where you think you got that?

This has come up a few times recently, and there's only two things we could find that look like anything resembling direct evidence:
1. Shadowbringers pre-release stuff that called the Eighth Calamity 'the final Calamity', but provided no real context or explanation, and never came back, so we really have absolutely no idea whatsoever what they were trying to get at (or even if they were trying to get at anything at all). Maybe related to G'raha's future, possibly?
2. The post-Antitower scene with Minfilia-Hydaelyn, where she explains the reasoning behind the Calamities; she tells us to stop the Eighth, and begins to say 'this is my final--' before being cut off; there's no indication what she would've ended her sentence with, but it's the sort of thing where a lot of people trick themselves into thinking she did finish that sentence.

You might recognize that neither of these sources are Ascians, so either you've got something we don't, or you're misremembering something. Understandable in both cases, it's a big game and there's a lot of stuff in it, sometimes we either forget a scene that happened or misremember a factoid until it becomes a scene that didn't. But when we hit things like that, it's in everyone's best interests to figure out what exactly we're dealing with and dig up whatever evidence there is. So if an Ascian did say it, we'd love to hear it, but if one didn't, then it's just as important to recognize that.

Seraphor's hit the nail on the head for why this theory probably got pretty common and had a few different breeds, though: reasonably speaking, there would have been a point where the Ascian plan changes, either because Zodiark becomes usable or because natural forces shift. If one then agrees this is an inevitability, then... well, why wouldn't the Eighth be that turning point? It's just as arbitrary and justifiable as any other number, but it also makes that 'point of no return' pretty soon, which is nice and dramatic.