>You can do per-display DPI just fine on X11 (through xrandr), it's just the major toolkits don't support it. GTK, for example, reads a single global DPI value from XSETTINGS; there's no reason why it has to be that way.
I remember people complaining about the GTK file picker not having a preview for more than a decade, and at some point it sort of became a meme.
When it finally got added, the PR was like a 2-300 lines.
And was added after they rewrote everything for the new GTK version when there're functional patches adding thumbnails to previous versions. (Which were rejected/ignored because they didn't feel good.) A situational very in parallel to Xorg/Wayland if consider: https://news.ycombinator.com/item?id=46382940.
I remember people complaining about the GTK file picker not having a preview for more than a decade, and at some point it sort of became a meme.
When it finally got added, the PR was like a 2-300 lines.