Link But doesn't dithering by gpu differ from dithering a display does? A gpu forcing dithering can cause flickering of pixels?
Yes, but even with on-display dithering algorithms (FRC) you'd see "snow" on a static image. I have an old ASUS monitor where it's blatantly obvious.
Link A gpu forcing dithering can cause flickering of pixels? Even on native 8bit or 10bit sources?
Ignore the 10 bit part for now, imagine a GPU always outputting a 6 bit dithered image to "make" an 8 bit image, regardless of what the monitor "says" it's color depth is. That's the issue.
Link Because if a gpu is sending out a signal to a display saying here's 256 colors bpc and the display has 256 colors bpc then what is there to dither??
See the above
Link If the panel is 6bit +FRC then flickering of pixels take place?
Or snow effect as I mentioned
Link Secondly does gpu ever even have control over display dither?
Not really, unless you mean forcing a 6-bit color depth, which means severe banding and unsuitable for image editing.
Link Anyway to completely turn off temporal dithering on PC since it's a open environment?
Depends on your graphics card.