Kana took like half a year break for university and in the meantime Tomoe had to deal with the same issue as takamori, where people stopped seeing them as separate people and acted like it's a couple channel, constantly asking her about Kana and begging for her to appear on stream. Which understandably pissed off both of them and basically killed the collabs prospects. They are still together afaik though so it's all good
Although I don't think it really works as example that I am looking for, because it wasn't like they both had massive unicorns fanbases, everyone was on board with the shipping from the get go. More like if it just comes out of nowhere and they have a ton of unicorns who thought this girls only love them