Image control at the UEFI level and then the operating system level - I'm exploring the topic...

I'm delving into controlling the image (displayed on the screen) at the UEFI level and then the operating system level. But I have lots of questions.

There is GOP (UEFI Graphics Output Protocol).
He appears to be controlling the image right from pressing the POWER button on the computer.
At some point, the graphics card driver takes over.
Is that so? Is there something else going on in between?

So the graphics card is in GOP mode, and then in the mode in which the image is controlled by the graphics card driver?

I am interested in the issue of resolution and refresh rate of the image transmitted by the graphics card to the screen.

How does the GOP control this? Image resolution and refresh rate?
When I turn on the monitor's OSD while in UEFI, it shows 2560x1440 60 Hz.

At some point, probably when switching to the operating system, the screen goes blank for a moment and then comes back with the correct resolution and refresh rate set (2560x1440 165 Hz).

Why does this screen blackout have to happen? Why can't it be smooth?
Why can't it be 2560x1440 165 Hz at the UEFI stage?
Anyway, when I set the system to 2560x1440 60 Hz (which is the same as the OSD says for UEFI), the screen goes out the same way.
So what does this mean? What exactly is the mechanism behind this, at the graphics card level?

Why do I need this knowledge? Out of curiosity...
Because in my case the screen goes off for 6 seconds, it seems like such a long time, it's the monitor's fault, it's just like that, and there are many monitors that just have it like that. But it's minimally problematic, and that's why I'm delving deeper into the topic...

Monitor Gigabyte M32QC connected DisplayPort
GPU GeForce RTX 3060 Ti
Motherboard ASRock A620MHDV/M.2+