Yes, but if it dramatically increases complexity for all the lower levels of the rendering stack, it ends up creating extra work for those OS/framework developers, requiring separate versions of the code targeting different displays which must be maintained separately with different sets of bugs in each, preventing them from making large-scale architectural changes they want to make, restricting some types of significant optimizations, etc.

Apple has a $200B war chest. If they can't afford to deal with this problem and instead choose to make my experience worse that says something about their priorities as a company.

You must realize that not all problems can be paved over via money and engineering bodies, right?

Their priorities is not just everybody (and has never been). It's high end users, who can afford $2/$K laptops and hi-dpi displays.

Do they always get things right for them? No. But those are their users, not the average joe.

Yeah but isn't it already a solved problem with 1x monitors? Who is implementing things multiple times for no reason? I'm glad in the future it will be easier for Apple because they just won't hire devs to do that part then, but does this imply that 1x monitors will simply look inferior no matter what is done with newer versions of OSX+?

There's a broader change that is an improvement to the abstraction devs work with, which simplifies coding and results in more GPU acceleration.

Essentially, this article: http://darknoon.com/2011/02/07/mac-ui-in-the-age-of-ios/ will be obsolete.

If it's possible to realise those benefits while retaining subpixel antialiasing, it would entail a complete reimplementation.

On the other side of things -- Light-on-dark subpixel antialiasing has always been a little wonky, and Apple disables it in most dark UIs. Without significant changes, dark mode would've been greyscale either way,

This complexity is why we can't have windows that spread between 1x and 2x monitors since the introduction of Retina displays.

Ideally everything should be rendered (and cached) to the maximum resolution available (minimum trace widths considered) and then downsampled to the specific screens with subpixel data applied, but that's a lot of processing to do and battery life would suffer.

Eh? Before Yosemite was released in 2014, one window could span between a 1x and 2x monitor. I forget if it was always rendered at 1x, or if it was rendered at 2x and scaled for the 1x, but yeah it looked like crap on one or the other. Actually I think it switched depending on which monitor had more of the window?

But they only eliminated windows spanning across multiple monitors when they made spaces per-display.

It's still there iirc if you disable separate spaces per display.

I don't remember that, but, if you do, I trust your memory (and your hypothesis) over mine.

It’s already a solved problem if you want to keep using the software you already wrote, and never do anything different. (Nobody is stopping people from running OS X 10.13 indefinitely on their 1x displays.)

If you want to rearchitect your whole text / vector graphics rendering pipeline to take proper advantage of GPUs, then you are going to be much happier with your life if you don’t have to double your work to support legacy hardware.

I would love to see Apple implement this kind of thing http://w3.impa.br/~diego/projects/GanEtAl14/