Angry Parent Rock, as it is deceptively called, actually has nothing to do with rock. It has a lot to do with screaming whiney bastards yelling about how angry they are at their parents. This style of music has been made popular by such bands as Linkin Park
Angry parent rock originated when stupid band members were finally allowed to write their own songs by their agents and managers. These band members, having the brain power of a 92 year old that has been dead for the last ten years, ended up writing an album or in some cases two or three with all songs consisting of no more than two chords and vocals with a mildly abrasive voice saying how disappointed he was in his father.
song writer 1: hey what if we did a song and the guitar went 'BAAAAAAAAA' then 'WAAAAAAAAA' 'WAAAAAAAA' then back into a 'BAAAAAA'
song writer 2: yeah that is sooooo cool and ill sing "FATHER YOU MAKE ME ANGRY. WHY WONT YOU DIE AND BURN!!!!"
song writer 1: (crying) oh why won't father support my music career.