No they don't; mediocre 'nice guys' do though. Every 'brilliant jerk' I've worked with and led has been a net positive over the long haul. Every mediocre nice guy has been dead weight that costs everyone around them time. I'll take the brilliant jerk any day. They can simply deliver in ways that others cannot.
Holy false dichotomy, Batman. I'd rather take neither of them and fill my team with adequate-to-exceptional devs who also happen to be decent human beings.