Slow monitor compromises multi-screen detection

[Hamlet]

Hello all,

I have a Gentoo KDE setup with two monitors, the slow one in the subject being a Samsung Odyssey G70.
The general issue with the latter is that it takes 8-10 seconds to change video mode.
It was just a minor annoyance until a couple of weeks ago. Then, I updated the system after about two weeks from the previous update, and got a new NVIDIA proprietary driver (515.76 -> 520.56.06), X components (I see mesa 22.2.0 -> 22.2.1), likely updated KDE, and finally a new Linux kernel (5.19.11 -> 6.0.2). After update, recompilation, installation of the new kernel, module recompilation and reboot, X or his lackeys would just decide that the Samsung monitor does not deserve join the virtual screen.
The monitor is there, we all know it, and if I insist to enable it, my setup tries, gets impatient and after a few seconds it gives up and the screen is restored to single monitor.
The trick I finally put together is to set up the monitors with a script which attempts the setup a first time (xrandr), waits 8 seconds, then tries again no matter what. In that way, the second attempt finds the Samsung monitor well ahead in the process of fulfilling the request from the first one and it completes the new request before the timeout.

I suppose it's hopeless to ask whether it's possible to make the monitor react faster, but I wonder if anybody has a guess of how to extend that X timeout to 8-10 seconds to give the time to the sloth monitor to get there.
Or even just where to ask: I don't understand if it's a driver feature, a X feature, a kernel feature, or a KDE feature, or a superimposition of them.

Video board is a NVIDIA RTX 3070, connection is via DisplayPort, the resolution of the monitor is 2560x1440.

P.S. I attempted to revert video drivers and use the previous 5.19.11 kernel together (including recompilation of the kernel modules) and the problem was still there. But when I run the even older kernel (5.19.9) which had still the module for the old video driver, the second monitor was "fast enough" as it had used to be. In this configuration, X and KDE were still the updated ones, only the kernel was an old one and the driver was a reverted one. I am not really sure what to make of it.

[Hamlet]

... and it went back to annoyance level with a recent update: that is, take long to switch mode, but KDE correctly tracks the monitors without forgetting any.
I did not try to investigate what was the update that won the day.