Jefferies analysts say a real AI smartphone is years away.Jeff Chiu/APThe iPhone 16 lacks new features and a new AI smartphone is years away, wrote analysts on Sunday.Apple's stock fell 2.3% after Jefferies cut its rating from buy to hold.Despite these concerns, analysts continue to see long-term potential for the iPhone.One group of analysts finally said what even some of Apple's fans have been thinking: The iPhone 16 was underwhelming, and it will take a while before a real AI smartphone is ready.In a note on Sunday, analysts at Jefferies said that the iPhone 16's lack of new features and limited AI coverage mean that it might not sell as well as other analysts hope.