I think you misunderstood me. I've actually worked in print. I've written and typeset more books than I can count using professional DTP software (and LaTeX too). I know a thing or two about fonts.

I do not expect a non-retina display to display fonts as beautifully as a retina display, just to make things clear.

What I'm saying is that fonts under Linux aren't bad to the point of being uncomfortable.

And just to make it clear: I've got Windows and Linux, on non-retina displays, showing the same sites. Linux ain't worse.

There's a big difference between saying: "Retina displays are better than non retina ones" and saying: "Linux font sucks".

Yup: not everyone is on 4K / retina display. We know that. It doesn't make font rendering on Linux broken.

Since you bring it up, my second sysadmin gig was head of systems for a printing company, late 80s - early 90s, where I brought them into the digital typesetting era. So I also know more than a thing or two about fonts.

But I suspect you bringing it up, and me responding to it, doesn’t make either position more authoritative. And given “I’ve written more books than I can count” it could be your discernment of numbers or bar for objectively counting things is lower. ;-)

About retina vs. non retina, I’d argue font rendering algos matter more the less resolution they’re working with, so are even more important on non-retina displays. I’d further argue MacOS regressed on this by killing off sub-pixel rendering in Mojave, effectively dropping support for non-retina.

On low quality displays, Windows and Linux could/should look better than MacOS. When they don’t, they’re “doing it wrong”.

I have to agree here. Font rendering in Linux is across the board noticeably worse than macOS. I still can't quite understand why.

Agree with what? That's not the original point. The original point was that Linux font rendering "doesn't come close to Windows or Mac".

You're all shifting the goalpost.

Nobody is saying that fonts on a retina display on OS X do not look better than fonts on a non-retina display on Linux.

What we're disputing is that fonts rendering on Linux is so bad that it's "uncomfortable".

Now we may have a discussion as to whether everybody should be using retina display or not but that'd be another topic.

I have a 2012 MBP and two other machines running Linux. I'm not talking about retina displays at all (I don't have one). The rendering difference is noticeable. "Uncomfortable" is exactly the word I would use.