So the screen resolution does not affect the current draw.
Thanks for starting the thread. It spurred me on, to read about these issues.
What you just said (I ONLY quoted the bit I mean), is both completely 100% right, and NOT, at the same time. Let me explain.
Thought experiment, to explain. As I understand it. If you have a 4k panel, and measure the overall power draw. Then, keeping the panel dimensions the same, magically change it to a (current technology) 8k TV panel. Although you are perfectly CORRECT, the panel/backlight will continue to use the SAME power.
Unfortunately, you will notice (from my background reading), the display brightness, drastically (badly) drop in intensity.
So, in order to force the overall picture brightness, back up to what it was, with the original 4k TV panel. It will be necessary to considerably increase the brightness of it. Which will usually result in a significant increase in power consumption.
This is because the smaller pixels (8k rather than 4k ones, fitting in the same overall panel dimensions), will in effect, have much bigger borders (relatively speaking).
I.e. Although they can make the pixels ever smaller, the borders, between the pixels, sadly, remain the same size (as I understand it). Probably due to technological limitations, at the moment.
So, proportionally, that forces (scientifically or mathematically speaking), the space for the smaller pixel to shine through, disproportionately smaller.
Or in other words. The display brightness, for a given amount of power on a 4k panel, will dramatically fall (be much less efficient), as so much light is lost/wasted, by the borders between the pixels, which HAVE NOT become smaller, because of current technology limitations.
N.B. That was my understanding, by reading up on it.