It does do something regarding Bill's powers since he is the one who caused and continues sustaining Weirdmaggedon with his weirdness powers.
Bill is said to get more powerful as Weirdmaggedon goes on as well, which aligns with Time Baby confirming that Weirdmaggedon also gets more dire as time goes on. So the two are definitely directly connected in a way that translates to AP.
- Wierdmaggedon immediately starts when Bill starts wrecking havoc.
- Bill gets stronger at the same time Weirdmaggedon gets more dangerous.
- Weirdmaggedon ends when Bill dies.
- Bill refers to himself as the host of the party that never ends (Weirdmaggedon).
The affects in other dimensions are supporting evidence for this not being a localized event isolated in space. Which is proof at the very least this is not some 3-A, single-universe threat, and definitely does help support other multiversal arguments.
Just to start things off, Weirdmageddon as an event refers to Bill just coming to Gravity Falls. It's not a separate phenomenon, so 'Bill gets stronger as Weirdmageddon gets more dangerous' doesn't really make any sense. 'Weirdmageddon ends when Bill dies' also doesn't mean much because Weirdmageddon is literally just Bill appearing in the real world. All of the environmental affects of Weirdmageddon were caused directly by Bill; they're just his powers at work.
Bill getting more powerful as weirdmageddon goes on doesn't suggest Bill is a multiversal threat at all, neither does Time Baby's statement. The 'affects in other dimensions' also add up to 'three rifts appeared in other dimensions'. Can't really translate that to AP at all since it'd just be range (and accidental range at that).
I don't know why you refer to this as a "sole justification" when that couldn't be farther from the case. You yourself refer to multiple 2-A arguments in this message.
Anyway, so you're using your own assumption to say Bill threatens the multiverse by travelling? This is a faulty line of logic since he would need infinite range and bare minimum Low 2-C to do such a thing. Which he doesn't have. 2-A is the only other option if he wants to threaten it's existence.
The claim that Bill only threatens to cause mayhem and chaos is also faulty since Time Baby confirms his very existence is already threatening to erase everything. So taking it as meaning destruction is the safest and most backed assumption.
"Likely" in your eyes won't cut it in this case.
Bill threatens the multiverse because everywhere he goes, he's bringing the lawless nature of the Nightmare Realm with him. Ford said that the realm's said lawlessness would cause it to self-destruct, and the rift causes the nightmare realm to spill into Dimension 46, which is extremely likely to be what Time Baby is referring to with "if your rip in this dimension continues, it could destroy existence". Bill can only travel to other dimensions using the rift, which would cause the nightmare realm to spill into them. When I refer to Bill traveling, it's with the rift.
Also, Bill doesn't need infinite range to threaten the multiverse? Going around wrecking havoc across the multiverse, causing dimensions to explode, forever (bill doesn't age) sounds like a pretty big threat lol.
You have to remember that being a 'threat' means that you're something that's likely to cause damage or danger. Bill destroying dimensions forever would make him a threat even if he can't actually blowup the entire cosmology.
Also Time Baby doesn't confirm that his existence is already threatening to erase everything. Time Baby very explicitly attributes it to the rift.
Can you prove that? Because, as mentioned above, the 'fabric of existence' is a very particular line that isn't ever used to refer to a single universe.
Why not? Time Baby doesn't have any dominion over multiple dimensions. As mentioned above in the earlier example, 'he could destroy existence!' in of itself isn't good enough to extrapolate said destruction to being anything higher than 3-A.
Still, "the fabric of existence" should bare-minimum be Low 2-C. Especially when this a statement coming from the Time Police, who say he is violating the laws of space-time.
Combine that with the evidence we already have of Bill directly affecting time in Gravity Falls, and the fact that his rip reached to other dimensions in the multiverse, and you get a feat that can not reasonably be scaled to 3-A.
But what is the feat? Time Baby attributes the universe's destruction to the rift because the Nightmare Realm would eventually destroy itself and that dimension. At absolute best you could say Bill's law manip was helping cause that but that still isn't a feat. And the rip didn't reach other dimensions: it just created a handful of other rifts as a byproduct. This is just how rifts work, because the rift
itself was a byproduct of a portal, it has nothing to do with Bill's actual power.
Anyway, the main proof for the Nightmare Realm stems from Bill shaking it.
Where is this from?