Setting 8-bit/16-bit color depth on macOS without using commercial apps

Can I set 8-bit/16-bit color depth system-wide without buying commercial software (e.g. Display Maestro)? I would preferably do this by editing system files, but a free app is OK too.

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:

> displaypacer list
> displaypacer id:<UUID> 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)