Well, It's set up that her agency aimed for pro-gamer VT, so maybe don't think of Holo or Niji, but more like VShojo environment? I can see her fans being like Sele- Dokibird's fans.
Agency or indie, Japanese streamers in general of either sex are careful about interacting with the opposite sex. It doesn't matter what kind of content they make - there is always going to be gachikoi. The question to a first-time collab would be, "Is your audience going to be okay with this?" However, there are guys and gals who are so loved that they try avoiding collabs or try to treat the other person coldly just so they could avoid getting flamed.
The thing with Hololive is that they're not strictly off limits; it's their fans that were toxic. You should have seen Matsuri's chat whenever she plays Apex Legends way back then.
On the other hand, the EN side of both Niji and Holo aren't aware of this "etiquette", so some of them have gotten the other party flamed for interacting with them. Then again, the OG JP had to learn it the hard way too back then.