In addition to
>>83759272 I think the chuuba's irl character also plays a role.
Aqua is an irl bocchi, adding that facet to her character. Subaru's bright personality is reflected in her on stream and off stream stories. Mikochi's Pon, Marine and Maturi's lewdness, all of it are "anime character" traits. And when they embody these traits both on-stream and in irl interactions, that's when you fully buy into the setting that these are actual anime girls streaming for you.
There can be dissociations as well. Shiori and Raora for example, cause a huge shock at the beginning when they revealed their voice and the initial impression was that it didn't match their models.
But people can get used to it as long as they have something else anime-sque to attach themselves to.
Shiori has played into the "weird girl" aspect of the goth girl model and kept her character afloat that way.
Raora tries as well, the "god eyes" references from time to time, the catlike behavior + purring etc. are good additions.
Normal streamers can't fucking purr on stream and get away with it, unless they're hot girls showing their cleavage.
But it's accepted as a completely normal thing in the VTuber sphere.
I'm quite sure there are a ton of weirdos in the 2view and indie spaces as well, but they never really embody the sort of "anime girl" personality trait that people expect from this medium. Some of them are blessed to have it naturally, but they often lay it to waste by lecturing or shaming their audience on some irl issue or another, or "set boundaries" and shit which is not something you see in anime.
And that's when the viewer understands that these aren't anime girls, just skinwalkers.
The lack of understanding of this aspect of VTubing in the EN sphere is the reason Hololive is still dominating despite all their slipups and the grim era.
