Isn't this the first time they have an actual zoom lens vs multiple lenses and thus CMOS?
Edit: reading below it's still unsure if they actually have a lens that moves back & forth to achieve the zoom.
It's probably the same as the 2x zoom in the iPhone 16 line. The 1x pictures are a 48MP sensor that does some pixel-combining to output a 12MP image. The 2x pictures are a crop of 12MP in the center of the sensor, that doesn't do any combining. So it's still "optical", but it's lower-quality than the 1x.
This is the first time they use linear (classic zoom) design. The previous one was a 90-degree periscope design. From 16 Pro Max specifications:
> 12MP 5x Telephoto: 120 mm, ƒ/2.8 aperture and 20° field of view, 100% Focus Pixels, seven-element lens, 3D sensor-shift optical image stabilization and autofocus, tetraprism design. 5x optical zoom in, 2x optical zoom out; 10x optical zoom range
An image showing what they did earlier: https://i.4pda.ws/s/as6yz0d0FvbZniF2YYSyZ3z2HOWajz2.jpg