I think laptop users rarely see much of their wallpaper, and that’s a significant fraction of users.

You could even argue that, if you see your wallpaper close to “all the time”, your monitors are larger than you need most of the time.

Jokes on you, I give my terminals a slight opacity so I can see the wallpaper all the time.

Sometimes I'll keep an empty workspace up just to declutter and focus on something on the other monitor.

Same - I always keep some opacity on my windows and I use gaps on i3

It's not necessary, I could as well set black wallpaper and no gaps, but I like it so it's good enough excuse ;)

It just feels good, like soft, indirect, amber lighting.

I agree completely. The best wallpaper is pure black. I haven't used anything other than black in ~20 years.

50% gray is the way to go. I've been doing it since we had to simulate gray by dithering black and white pixels.

I agree. Black and white often pop up against certain types of content (e.g. white spreadsheets on black background, dark mode terminals on white), but gray's a good compromise.

black wallpaper will be awesome for battery life once OLED laptop screens come out

It's not really true that black wallpaper saves battery. Black wallpapers have been shown to make almost no difference on smartphones.

I mean I guess if your primary use of your laptop is sitting on the desktop with no windows open, just staring at it?