I think it s a mixture of his love quest and his parents. The fact that his parents were so paranoid of getting the proper care for their son and for spoiling him. His love quest also showed how vulnerable Chris was in getting a sweetheart, which lead to majority of his videos.
If Borb raised their child properly he would have had every chance to be at least a basic (if rather odd) contributor to society. Instead, we got the Chris we know and love today.
But in the spirit of the thread, I'll say Sonichu. It's what made the internet aware of his existence.
Untreated Autism+Trolls discovering him after Sonichu+Love Quest = One fucked up individual.
He has never been shown on how to over come his autism: Parent fail.
Sonichu getting leaked on ED and 4 Chan: Bringing the attention of the worst the internet had to offer, plus his inability to let shit go. If he would have just let it go it would never have ballooned
Love Quest: Repeated encounters with Jerkops and other various authority figures ending in arrests and bans from various local establishments.
Without the internet he would have been a random kook anyway.