Okay, tracked down this[0], which is probably what you were talking about(?), and what the actual fuck is wrong with that rendering engine? You render a Apx horizontal line, Bpx of space, a second Apx line, Bpx of space, and the third Apx line, where A=B=1. Maybe you use 2px of space. Maybe, if you're rendering obnoxiously huge, you use a 2px line and however many pixels of space. You don't fucking use real-valued vector coordinates and then blindly snap them to integers, or smear bits of gray anti-aliasing around the screen like some kind of monkey with a hand full of it's own feces.
If OSX is actually doing stupid shit like that, it's no wonder sane-resolution moniters look like crap. Stupid-absurdres monitors will look just as bad, because the problem is the operating system driving them, not the monitor.
0: https://tonsky.me/blog/monitors/hinting_failures.png