Earlier quoted context omitted.
I have collected a long list of these types of settings over the years, for example disable font smoothing: defaults -currentHost write -g AppleFontSmoothing -int 0 It used to be a checkbox, now there's only this command. Eventually that will be gone too, and none will be the wiser except the old who remember the good old days. I'm starting to think these settings are left there by rogue engineers who fight against t…
what is the purpose of disabling font smoothing?
macOS applies something called "font smoothing" (image) which is adding a layer of pixels to your text. The effect is that text is made a little more bold—not "bad" but it isn't exactly as the typeface designers intended.
Here's a good example:
The thing about 4K on macOS is that its sharpest setting will be when you make it "look like 1080p" which means its sized like a 1080p monitor but its 2x sharper. If you make it "look like 1440p" which is what you're used to, macOS will draw a 5K image and scale it down to "look like 1440p" but it doesn't fit the pixels on your display 1:1, so there is a slight blur or its not as sharp as native "looks like 1080p"—but it will still be sharper than your 32-inch 1440p display, so I still recommend you move forward if sharp viewing is a priority. The only sharper alternative is to buy Apple's 27-inch 5K display at $1600 (although $1300 refurb) or a 32-inch 6K display (Dell and Apple make them).