XAI cofounder Jimmy Ba said he left Elon Musk's startup on Tuesday. "It's time to recalibrate my gradient on the big picture. 2026 is gonna be insane and likely the busiest (and most consequential) year for the future of our species," Ba wrote on X. Ba reported directly to Musk. He ran a large portion of the company until late last year, when several of his responsibilities were split between two other cofounders, Tony Wu and Guodong Zhang, people with knowledge of the move told Business