If anyone is old enough to remember when the Columbine shooting happened, that's exactly what happened. Maybe not that he necessarily supported it, but his music and imagery were scapegoated as being a significant influence.
Now, did it have much of an impact on the music industry? No, it didn't. However, record labels have a lot more money and influence, especially back then. Not that I think that vtubing will be noticeably affected by this or anything, but it is certainly more vulnerable than the music industry was--and vtubers are ultimately beholden to the whims of the skittish platforms they stream on.
I agree with your position.
I think the reason why Ana Valens and Saphera de Noma takes are weird, besides dickriding each other, is that, and trying to steelman their position here, they are worried about vtubing being blamed by normal society for creating murderers like it happened to Doom. The shooters of Columbine were Doom fans, they even created maps. But the difference is that in that situation, Doom Fans didn't put the blame on the community for how the normies reacted. Here Valens puts the responsibility on the community for this one dude.
We know that if the press blames Hasan Piker for influencing Elias Rodriguez in killing that 2 israeli diplomats, Valens is going to call those journos dumb, and not ask for a change in the Hasan Piker or Breadtube community.
And a “community” in the case of vtubing, doesn't exist. People reunite in agencies or groups of vtubers but not in "general vtubing" because that is just a format of expression with not really much ideological connective tissue like breadtuber, so why this fearmongering?
The girls of Vshojo or Hololive are not going to lose opportunities because a dude who was arrested have some Pippa merch. Valens have been, since the Vallure shit ,trying to create this weird frame of “we are all in the same boat so if someone is a bad actor, we all go down”. When in reality there are multiple boats. When Nijisanji do bad shit, that affects the Nijisanji vtubers not some indies like Bao.
It is clear the objective here, to make other vtubers care about the things Valens cares about by fearmongering that if the “issue” is not solved, everybody will pay and will lose sponsorships, lose money.