>>30718733>orange hair>goofball face>iconic accessory>identifiable outfit>character lore and thematics (yakuza dragon woman who recklessly waves gun around) were appealing>funny man interactions with other holos>in the right company at the right time to get noticed>had a backlog of translated clips for people to get caught up on what her content was like>streamed as a vtuber the whole time, maintaining immersionIMO, Kson's issue (at least the one within her control) isn't that people know who she is, but rather that she's a facecam streamer who directly transitioned to a vtuber avatar. It's not a different character with a fresh start, and is completely meta, which means it's like starting to watch One Piece starting with episode 240. If you weren't watching up until that point, you missed so much it kind of feels like it's not even worth getting invested at this point. This is why changing things up and trying new things is important.
Likewise, while her dynamic with more straight laced JP vtubers was interesting because of the culture clash, she's relatively unremarkable as a solo streamer by twitch thot standards (or rather, twitch vtubers are universally unremarkable). And because western vtubers are also western, they won't be able to offer enough of a contrast.
tldr She didn't establish a new a new character separate from her regular streamer identity, and pigeonholed herself as a manzai comedian who only really stands out when a good tsukomi is present. Not that I'm a vtubing expert, but that does seem to be (aside form the factors outside her control) why she declined harder than she otherwise might've.