Elon Musk is pressing top AI labs and Chinese companies to cross-test their systems. He delivered that message while some in tech are calling for a slowdown in AI work. Musk himself holds big stakes in AI ventures. Tesla stock fell after the appearance. Musk also featured at the top of Forbes' yearly list of the wealthiest Americans. He repeated his proposal to merge Tesla and SpaceX. In a separate development, reports say abusive material involving children remains on X, even though Musk vowed to tackle it.