They hate Kirsche because she can see through their bullshit and knows exactly how to deal with them. It's not just her being informed on DEI bullshit and the social media mobs, she also knows that the only way to deal with them is to fight them on their ground and never apologise because they will never be happy, they will never forgive, and they just want you destroyed at the end of the day. She's clearly dealt with em before and knows how to handle them without turning people against her.
That's why Kirsche is probably public enemy #1 to the "woke vtuber fans". A cringey vtuber talking about how they like piss and loli or some shit isn't a threat to their power. A spicy fox who's appealing to normal people, stirring them up and making them aware of their BS. That's a definite threat.