Your colours are missing from recordings and clips
The game looks exactly how you want it. Then you watch the clip back and the colour is gone. This is not your capture settings being wrong — it is where in the chain the colour is being applied.
Why the recording is grey
Colour set in a graphics driver is usually applied at the very end of the chain, on the way to the monitor. Recording software reads the screen earlier than that. So the frames it captures are the ones from before your colour setting was applied, and the clip comes out looking like the app was switched off.
Gamma is the same story, and it is why brightness tweaks often fail to show up in recordings either.
Change how you capture
In OBS, use Display Capture rather than Game Capture. Game Capture reads the game directly and never sees anything applied afterwards. Display Capture takes the composited desktop, which is much later in the chain.
This one change fixes it for a lot of people on its own, and it costs nothing to try.
Or move the colour to where capture can see it
PlexusX has a setting for exactly this, on its Settings page: Move my colours where recording can see them. It shifts the work out of the driver and into a layer capture software reads, so the clip matches the screen.
The app also tells you when it thinks this is happening to you, rather than waiting for you to notice a ruined clip, and there is a button that tests your setup and reports what it found.
PlexusX runs on Windows 10 and 11. The download is free, and so is saturation with an account; the rest needs a plan.