Why is Bjorn hated so much anyway?
It has been said by fans that he was jealous of Mike Hoge or didn't want to be under his shadow, because he saw Gothic as something that belonged to him.
So he wanted to distance himself from Gothic by forcing PB to focus on Elex, because Elex truly belonged to him, even though that wasn't what people wanted.
Basically he derailed PB by petty jealousy/rivalry/ego trip, which is surprisingly common in the game industry. No one hates a game developer more than one of his colleagues.
But that's just a theory.