It's not optical zoom, it switches cameras. That is why it goes straight from 1x to 2x and there is no in-between, while there are fractions between 2x and 6x, for example. There is no in between, because the phone doesn't zoom at all on the main camera of the 7 Plus. It throws you immediately to a different camera, which, due to the design of the lens, has a naturally "zoomed in" view.
That's not optical zoom. It's simply camera switching. Any phone with two cameras can do that, and anyone with a camera and multiple lenses can do that by simply switching to a longer lens ;-)
There are phones with real optical zoom, like those Galaxy S Zoom devices Samsung released in the past, but I don't think that's something most people would want to carry around
Honestly, I'd rather a much larger single sensor and algorithms for pixel bundling, etc. to produce higher quality photos, similar to what Nokia did on PureView Phone. Also, better microphones and sound for video.
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And that picture linked a few posts after this one looks absolutely awful and unnatural.
But I guess that's why Samsung cameras phones are considered "tops" now. People really do seem to prefer oversaturated, unnatural smartphone photos. They'll even take photos from a camera that produces more "natural" tones and make them look like they were shot with a defective Galaxy S7.