The reason that answers on the linked post do not answer this question:
NONE of them address the use of the user's prefers-color-scheme setting which is the root and CLEAR difference between this question and why it is worth asking.
Original question:
Now that a majority of users in the world (currently over 75%, per: https://caniuse.com/#feat=prefers-color-scheme) have the ability to have the browser identify if the user prefers light or dark color scheme, how about having the Stack Exchange network respect that? It's actually an accessibility issue for many users as well as power saving for mobile devices to respect the user's preference for a dark theme.