OpenAI co-founder Sam Altman showered praise on Apple Vision Pro, joining the ranks of James Cameron, former Apple CEO John Sculley and several others who have endorsed Apple Inc.’s (NASDAQ:AAPL) mixed reality headset. What Happened: Altman took to X to share his excitement about the Vision Pro. The $3,500 mixed reality headset went on sale earlier last week. “Vision Pro is second most impressive tech since the iPhone.” It’s not just Altman who has been left impressed by the Vision Pro’s technology. Acclaimed movie director James Cameron said he was “blown away” by the Vision Pro, in an interv…