As far as I'm concerned, not all windows require the same level of privacy, so different solutions for different windows are in order.
Upstairs in the loft area, I thought the right solution would be something like cafe shutters. Like the ones that were popular when I was a kid. Cafe shutters only cover the bottom half of the window, leaving the top open for light. None of our neighbors are higher than us, so I'm not really worried about anyone seeing in the top half of the window. The slats on those cafe shutters from my childhood are usually pretty small by today's (shutter) standards. It gave cafe shutters a delicate and charming look. But I haven't been able to find them in a version I like. And I didn't want to part with that much of our money. And I have a lot of windows. So, I started thinking about some sort of alternative that would cover only the bottom half of the window. Something less fussy might be better, anyway.
Then, I came up with the idea of a window panel. I would use a canvas frame - that was half the height of the window - and stretch some translucent fabric over it. I'd find some sort of hardware to attach it to the window frame. It would be like the ceiling of the Cy Twombly Gallery. On my window! In Denver! (When you know me well, you know I recycle this inspiration from the Cy Twombly Gallery Ceiling every one point three years on some project. And I think of it as New! every time.)
Now, here's the thing about someone who is (admittedly) contrary in nature. You have to be really careful what you say to her. If you tell her that white window treatments look like underwear...her brain might start working overtime on that idea. Next thing you know, she's buying pantyhose and stretching them over canvas frames.
But if your mother is a professional artist, then it probably doesn't seem too entirely weird that your wife does things like this. And maybe you even encourage your wife a bit, by telling her it looks kind of good with the "diagonal lines." Nobody will know what it is.
And it does look kind of cool. Did you notice how the double layer of fabric creates "depth" with shadows as well as a moiré pattern in the photo above? That's cool. But the pantyhose? They're just not working at a macro level. I can't buy them big enough for the desired frame. And I don't have a solution for the pantyhose legs (yet? see photo below). I remember seeing some sort of knit tube material as a child. Decades ago. In an outlet in North Adams, Massachusetts. That's quite a drive from Denver.
And the canvas frame? Not working so well either - definitely needs to be painted white - and kept square. Somehow. Hmm.
I'm still upbeat on this experiment. I think there's something salvageable here.