In doing some searches on the subject this [1] came up. So there seems to already be movement on this front, and it's possible my knowledge of the current situation is stale.
There's definitely some level of gamma/color correction funtionality at the DRM level already in the kernel [1]. So my desires may already be largely fulfilled, and maybe userspace just needs to get its act together.
[1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/lin...