Um...probably because it's several thoughts together.
I find nkirbit a little scummy. His overall play seems "off". Going from "whole case on sudgy is neutral" to contradiction->vote, to contradiction explained->unvote, it's all neutral again, popping onto xerxes for voting ash, then popping onto sudgy for "panicking", finally sudgy-vote confirmed because he said nkirbit's vote "made sense".
I also disagree with him on a couple of his points regarding sudgy:
I disagree on the panicking thing. I think town often gets bogged down in defending themselves, while scum is often on the lookout for an alternate lynch. Any lynch which isn't a scum-mate is good for scum, while town doesn't particularly want to deflect onto another townie. If there were another wagon out there, I would expect sudgy to be on it, because they have a higher chance of being scum. But no one's really found a compelling case outside of sudgy (by which I mean one that's caught on) to call sudgy scum for his inability to do so seems wrong. It's not like he hasn't been voting or giving reads, he's just not finding a compelling case.
The "confirmation" thing I think is misplaced also. I mean, any reaction to a vote can fit a scum-tell. "You're voting me for terrible reasons" fits the scum-tell of scum that's caught for what they view as bad reasons. "You're voting me for good reasons" fits the scum-tell of scum that can't really defend itself, so acknowledges the case in hopes of it disappearing.
I don't think calling out someone voting for you for good reasons actually fits the "voting for good reasons" scum-tell. That scum-tell is usually more along the lines of "I acknowledge the overall case against me, I just think it's wrong". Sudgy is largely in the first "scum-tell" camp. Calling out one prosecutor to say "you make sense" doesn't achieve the desired result of acknowledging the suspicion against you.
If anything it's just still part of the first scum-tell. i.e. scum-sudgy views the wagon on him as existing for "bad reasons", but acknowledges that at least one person has gotten a "good reason". To me it just stops being scummy at that point. It's not part of a scum-narrative any more, it's part of a reasonable reactions narrative.
As a result, I don't find nkirbit's reasons for voting compelling. But ultimately, that's not why I'm voting for him. The reason for my voting is because the line of activity seems off to me...jumpy maybe? Wanting to be on the wagon, but worried about joining it for the "wrong reason"? I think that's the gist of it.