Can you expand on that? Did she make irrational comments, accuse people of impossible acts, was she threatening? I looked at the 1.5 minute video someone copied out and she was upset but not frothing at the mouth.
You don't have to be "frothing at the mouth" to be mentally unstable. I saw her videos on Dailymotion and I had the impression that something is not right with her, can't really pinpoint or explain what it is. but definitely very awkward in front of the camera. Just my personal take on it.
You mean like Poppy who has millions of views on youtube? If you saw her before she was known you'd probably think she was just as likely to shoot up youtube HQ.
The truth it's not as easy as it seems to separate the "merely deviant" and the violently deviant. That's why censors often choose blanket censorship of any deviance.
Arguably the only reason Poppy got popular was because people weren't sure if she was an act. For a long time she was just "OMG who is this freaky youtube girl!!!"
Obviously in hindsight we know she was an act and correspondingly interest in her has declined.
Blurring the line between act and reality is one of the foundations of entertainment. It's the reason people admire good method actors so much. It's the reason people like Andy Kaufman are considered artistic gods.
My rule with Youtube is that, if the production value is relatively high, the character is an act (ie, scripted). I don't know who poppy was had to look it up and saw some of her older videos and it seemed to me that right from the beginning her videos had good lighting, makeup, dress code and overall editing quality was higher than your typical amateur youtube videos.
As someone else mentioned below that easy to have an opinion after the fact, my observation of the shooter, as well be biased, but I feel that even I didn't know anything about her - I would still think the videos were odd. I can't exactly pin-point whats odd about it.
I watched one video. It's possible that something was "not right with her" but then I think that's true in some small way with almost all of us (personality foibles, etc).
But it's also possible she was on-edge because she was angry and frustrated by a situation that was important to her (earnings, passions, etc). Lots of people act like that when they feel upset, then you add in the pressure of a camera...
Her entire personality was based on being vegan.
She considered herself to be someone from an alien planet sent to earth to suffer.
She criticized all the suffering around her and explained how nobody could understand her.
She was apparently against anal sex.
She hated women who used their body to get places. While she herself did do that (explicitly said so) in her videos.
She thought there is a conspiracy against her "truth".