Of course. If you disable it in settings, you should see a noticeable boost in batter life (~1–1.5 hours in my testing).

I wonder if turning off the blur/transparency effects in iOS results in any substantial battery difference...

It does, yes, but less substantial than on Mac, due to tighter vertical integration between software and hardware.

Can you be more specific? What exactly do I need to disable to see a battery life boost?

It's right there: https://news.ycombinator.com/item?id=14948178

You need to enable the linked options which in turn disable some visual effects.

forgive my ignorance here (new to Mac), but which setting is this specifically?

In System Preferences, under Accessibility -> Display, there are two settings of interest: “Reduce motion” and “Reduce transparency”. The latter is the more important.

try in settings->Accessibility->Reduce transparency. this will also make the OS more responsive (minimizing, switching windows....)

Are these effects active also in "steady state use"?

Normally yes -- a bit similar to e.g. when a game is displaying a seemingly 'static' image (when you don't move your character), then the GPU is still rendering at X frame/second.

What?! That sounds like something I would write as an amateur. I thought that modern graphics systems would be smart enough to only render when the screen has actually changed. I.e. a tick still comes at 1/60 times a second, and it checks if a region is dirty, but the whole copying of textures and re-compositing (which practically doesn't take time - or rather fixed time - and runs on the GPU, but costs power) is only invoked when something is dirty.

Actually, I remember reading something that Windows doesn't do any blitting / buffer swapping if you just leave it idle and no updates happen on screen. However, there are many ways to throw this off and force drawing every frame if you are not careful.

Yikes, that would indeed be the first thing to fix on a battery-powered platform then.