Saying that ALL vtubers read /vt/ and possibly TVA seems very, very optimistic in my eyes. There are way too many normie vtubers that recoil at any sort of imageboard culture to bother reading /vt/, especially since that board has a terrible reputation for anyone not autistically obsessing over vtubers, even those who browse other boards. And reading SEAn!gger schizo opinions hardly counts as "honest criticism". Bothering to dig through shit to find some worthwile takes is way too much effort. TVA is less known but at least more tolerable since not everyone is thirstposting. Sure, those two are some of the few places where people talk about vtubers, but I'm pretty sure most of them stick to namesearching themselves on twitter. Hell, I wouldn't put /vt/ much above twitter by the cringe that is posted. The only thing missing is the reply guys.
But I can definitely imagine pcg girls being drawn to the board and maybe even TVA, since they are all their own kind of special. I wouldn't apply Pippa and Kirsche as the broad standard though.