This is pretty true to a portion of IRL idol fans, especially on twitter. the vicious fans tend to stick to imageboards.
Also I always find it funny that her non-idol form is supposed to be some huge lapse when she already has a jirai/alt-idol (which is more popular than orthodox idols these days anyway) look as an idol with the hair and all. she honestly just looks like Kashii Katy, an alt idol it girl who'd regularly get 10k likes on selfies holding a cigarette.