That’s not surprising. The 11 uses an LCD and the 15 uses an OLED. So because the display technology is different they’re bound to be different from each other.

Normally this isn’t be a problem on Android’s because you can adjust the display warmth to your tastes. Unfortunately, because iPhones use True Tone; the hardware/Software adjusts the warmth of your display. Theoretically with True Tone enabled, both the 11 and 15 should be close in terms of warmth. Unfortunately that may not necessarily be to your taste.

One to two. Typically keep my phone 4 years.

Zero likelihood; because:

1. Apple is a bunch of control freaks.

2. Apple doesn’t have the programming chops to figure out how to do it.

Take your pick.

Zero!

This isn’t really anything new; this has always been the case with Apple.

There is nothing that you or Apple can do about the viewing angle, but as for the color temperature, there’s a lot that can be done; but Apple won’t let you.

If you ever used an Android; then for the most part you can adjust the color temperature to your preferences. Unfortunately you can’t do that with iOS.

I personally don’t really notice the difference, unless I compare the screens side to side. Usually I just get used to the screens color temperature; but some people just can’t.

iPhone Display Color Temperature Comparison

Don’t be silly. The difference in performance between the pro and no pro versions is negligible. They both will receive the same level of support.