Well, it was a white guy. Maybe he was upset by posters... I hear that can drive people nuts.
Of course, when a white guy goes on a racist shooting rampage, we often get this speculation about his mental illness.
Such as this.
Dylann Roof has mental disorders, attorneys argued | CNN
Dylann Roof, convicted of killing black parishioners at a South Carolina church in 2015, suffers from numerous mental disorders, a now-unsealed court document says.www.cnn.com
or this
"Well, it was a white guy. Maybe he was upset by posters... I hear that can drive people nuts."
So stop posting and reading posts then.