Tamsin McMahon / Bloomberg : xAI co-founder Toby Pohlen is leaving the company, the seventh of 12 xAI co-founders to depart; Elon Musk put Pohlen in charge of Macrohard earlier this month —  xAI co-founder Toby Pohlen said he is leaving Elon Musk's artificial intelligence startup, the latest founding executive to depart …