This is great, would love to see a similar way to do it in Android.

There's likely a way to do with via Tasker/MacroDroid but you'll likely need to use Shizuku (or possibly root) to change these system settings.

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Groxx 4 hours ago | parent | prev | next [-]

I don't know of any way to control the setting automatically (sometimes there are special-permission non-standard/undocumented intents for settings though), but as a maybe-close-enough you can turn on grayscale color correction (in accessibility -> color & motion, in my phone) and add a quick-settings tile to toggle it.

	▲	froindt 3 hours ago \| parent \| next [-]
		I'm on a Pixel 10 for these instructions, not sure if other manufacturers offer the same options. Modes is an available option in the tile list. You can go to Modes, create a custom mode, and under display options you can set greyscale. You can also set modes to turn on automatically based on calendar events or a schedule. Notification tweaks are also available in the same area.
	▲	striking 4 hours ago \| parent \| prev [-]
		You can also use one of the accessibility shortcuts to trigger it quickly (both volume buttons held, triple tap, two fingers from bottom) if so configured

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rubslopes 3 hours ago | parent | prev [-]

Samsung routines can do this.