So the big problem is that even when a display reports that it can produce 8-bit (or 10-bit) output, many cards/chipsets are "locked" in dithering mode. AMD/ATI is notorious for this. There used to be a registry hack to disable dithering but it looks to have been removed in later versions of the drivers, maybe? I don't know, as I haven't had an ATI card in a long time.
Macbooks are also notorious for this. You can plug a Macbook into the nicest display known to man and it will still dither, no matter what, in all modes. Nothing to be done about it unless JTL is successful in figuring out his kext injector.
And no, plasma dithering is not achieved by rapid pixel flicker, but rather by SLOW pixel progression. This is annoying to some people, but you can literally chase the moving pixels around with your finger on a plasma, which indicates that they're cycling at rather less than 60hz. It's ... sort of ... a combination of temporal and spatial dithering. Like a moving spatial dither. To me it looks more "natural" and my eyes tolerate it very well. But to others it's crazy annoying. You're supposed to sit far enough away that you don't see it, though.
OLED dither is achieved the same way as LCD, yes.
Last response (I hope I've hit all your points) is that I have no idea how the new nVidia chipset will perform on the Switch. I have used several Switches, but only in handheld mode. One was gorgeous and easy on my eyes, one was ... fine ... and one was slightly painful (like using an iPhone screen). Since all of them were running identical software, that leads me to suspect that the panels are not the same. Perhaps they use several manufacturers as they are attempting to meet demand? Or perhaps the ones that I liked less were newer, and they've cut corners to meet demand? Either way, I would expect that since at least one of the panels was ok for me that the output to my TV would also be ok? But I don't know for sure, Nintendo is odd - the WiiU has had its ups and downs for me but the handheld unit is ALWAYS fine, albeit being only 720P with I suspect lousy display characteristics (slow refresh, bad vieweing angle as compared to the switch).