Yes as I have already said Samsung also made the Super AMOLED Panels for the Pixel and Pixel XL, which many LCDs including those on the iPhone 7 are better. Just because Samsung are making the panel doesn't mean Apple will get the same quality panel as the Note8, it may get one equivalent to the Pixel.
Then there is the V30, OnePlus 3/3T/5, Moto Z Force 2 - all of which have very good panels but are certainly not better than the best IPS LCD's as they all have issues either with subpixel clarity / softness, outdoor visibility, uniformity etc ...
Why OLED for iPhone 8.
They likely I sumise chose OLED because of the way each pixel is lit independently and with no need for a separate backlight would allow for more reliable uniformity given the iPhone 8 is using an unconventional shape with cutouts, which an LCD and it's backlight would potentially struggle with.
Here is a prime example where a display technology (OLED in this case) is more suited to the device, but that doesn't automatically guarantee a better display compared to other LCD's in general terms.
I honestly have answered this a dozen times now on this thread even I'm becoming bored of the subject
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We can only hope Apple obtains a panel with the quality of the Note8 or S7/ S8, albeit colour calibrated more towards Samsung's SRGB Basic mode given Apple prefer realistic colours generally.
If they do it's win win, but it is not guaranteed they will get a panel from Samsung as good.
But this is all by the by. This discussion and importantly (so I will reiterate) the point I was making was on the general presumption asserted and declared here repeatedly that ALL OLED ARE BETTER THAN LCD which is definitely not the case.