@AlanSmith I'm not sure what your source is for this list you've compiled, but it's not entirely accurate.
The S2522HG, for example, as per this review is not a true 8-bit panel as you've mentioned.
In particular, the LM245WF9-SSA3 that is.
It uses static dithering, leading to a green tint (check review, use google translate for more information)
Oh, and something which people on this forum completely neglect is the description of lagom.nl in regards to dithering:
Source: http://www.lagom.nl/lcd-test/black.php
For anyone coming across this list above, be cautious.
Oh and also, output depends on the GPU used.
Non-Quadro, RTX 30 series and below do not support true 10-bit output (from what I've understood)
I don't know how AMD is in regards to this.
Example of S2522HG (6bit+FRC - static dithering, LF245WF9-SSA3) VS AW2521HF (true 8-bit, M250HAN01.7)