There are apps that change a smartphone screen to be greyscale only. Probably not as good as not having one but it might reduce the addictive quality substantially, worth a try in any case
If you're an Apple user, it's built-in, and I've found it ergonomic to assign its toggle to a triple-tap on your phone's back and/or laptop power button.
Those triple-taps are effortlessly quick and rarely if ever misfire, making it totally reasonable to stay in greyscale by default and reengage color selectively when you're looking at something that merits it (film, family, friends, a Wordle scorecard...)
On LineageOS, it's been a regular setting, with a quick tile, for quite a while. And in recent mainstream Androids (12, I think?) it's available under bedtime settings or something.
That’s a great idea. I tried a lot of similar techniques years ago without much success, but I should try again since I’ve been diagnosed and treated for ADHD since then.
