Possible Fix Flickering/Grey-Grid/Checkerboard on M2 Mac Mini with Lenovo Q24H-10

[ripinpeace]

Me like many others have faced the issue of M1/M2 macs flickering when connected to monitors.
I've tried every trick I've seen here and elsewhere, without fix.

I read the benQ help page trying to get a sliver of information and they mentioned something about refresh rate sync issues, it got my noggin going and I started testing other things.

First off problems persist USB-C or HDMI, haven't tested DP and probably wont.
After a fresh reinstall of MacOS and my eyes once again being pained by the flickering vertical lines.

ONLY THING THAT HAS HELPED ME.

I was playing with resolutions, setting to mega low resolutions, and noticed that there was no more lines, grid, etc.
Then tried 1920x1080p, flickering again. While still in 1920x1080 i went into the OSD of my Lenovo monitor and I noticed it still says i'm on 2560x1440, interesting I think, then I start setting random resolutions and notice that if the resolution sets and is registered also in the monitor OSD, there is no flickering, if it says the 2560x1440 it flickers. 1920x1200 for example registers and doesn't flicker. It's the highest one for me.

Also when switching to the resolutions that register and don't flicker, the monitor goes black for a second, as opposed to when it doesn't it is an instant change without going to black.
I'm placing some suspicion on refresh rates. For example when I am on 800x600 on 75hz, I check OSD it still says 2560x1440@75hz, I switch to 72hz or 56hz screen goes black, I check OSD and it's 800x600 and flickering goes away.
Also have a suspicion this is somehow linked to the problem of 75hz not working over HDMI by giving "NO SIGNAL"

I'd like some input, what is the reasoning behind this?

Results observed on a HDMI cable, USB-C has the same results.

I hope some other people who have this problem can test and see if this works for them too.

 

[ripinpeace]

Been playing more with resolutions with better display, I'm trying to see if I can force 2560x1440 to 50 hz or 56 hz somehow or even 72 hz, closest thing so far I have gotten is 1920x1080p with 50 hz and then adjusted resolution to 1280x720, forces it into hidpi which looks sharp and doesn't flicker, problem is everything is too big.

Closest thing to solution right now:
1920x1080@50hz mirrored with betterdisplay, the size of everything is like it should be in 2560 but blurrier, at 1080p. But with a new problem: mouse doesn't work half the time. The pointer disappears and reappears.

EDIT2: New revelations, I believe pixel clock is maybe the cause? On SwitchResX 1920x1080@50hz says pixel clock 148.50 and that res doesn't flicker. But for example 1920x1080@60hz says 148.50, but when you switch it on it says 241.50 and flickers.