Setting 8-bit/16-bit color depth on macOS without using commercial apps
Check out displayplacer: https://github.com/jakehilborn/displayplacer

It's a command line utility, but it works great and is quite simple to use. Example:

&gt; displaypacer list
&gt; displaypacer id:&lt;UUID&gt; res:3008x1692 hz:60 color_depth:8 scaling:on


And as a CLI utility you can easily script it.  For example: When I switch off of AC power, I have a script which automatically calls displayplacer to switch my resolution to the default retina resolution giving me very slightly improved performance/battery life)