The reduced-resolution thing has been a trick for ages, I just refused to use the 4k screen I paid a premium for at half res with horrid (seriously, horrid complete with artifacts and fuzz, I even patched xrandr to disable bi-cubic filtering trying to make it ok and still couldn't stand it) looking text aliasing.
I'm impressed you'd call that "pretty much perfect and comparable (if not better) to macOS with a recent distro"
Pretty much sums up why I don't think I'll ever really be ok with a Linux DE for daily usage. If that's what your users consider comparable to macOS why bother aspiring to reach macOS's perfect (seriously, perfect, even when you mirror across a low res screen and a high res screen it lets you use the high res screen at a higher size with perfect scaling) handling of any mix of resolutions.
4k at native (unless you're using a single, >30 inch display) is too small. I use two 4k, 28 inch monitors and everything is too small at native resolution.
I ran in to a lot of issues doing the xrandr downscaling (my two displays would overlap), so I've just been using Windows partition since this is my gaming PC. My linux partition is Arch, I hope Gnome supports easy fractional scaling soon. Something similar to the display scaling menu on Mac OS would be really nice.
That was amongst the fixes I found on stack overflow, and it was nearly identical as far as issues. Maybe I'd have been ok with comparing that to Windows (where some programs do get scaled down if you start them on a high res screen and move them to a low res screen), but macOS is the definition of perfect handling of multiple monitors. These tricks don't come close to that experience for me, let alone exceed it...
Downscaling works fine for me, so I don't know what I'm missing :)
It's probably going to look better with Wayland's per-screen DPI setting, but in the meantime, it's good enough (tm) for me.
Why Linux font rendering exceeds the macOS experience for me: I like the FreeType rendering much better than macOS - less "blurry". Probably comes down to taste. Unless I'm mistaken, macOS scales down for non-integer sizes while Gnome can be configured to render at a fractional value.
Obviously it's much more polished in macOS (otherwise I wouldn't have had to type out the tutorial above), but I'm using Linux for other reasons beyond that and having good font rendering is just a plus - it used to much, much worse.
I mentioned in another reply, that's just the flip side of the fixes I mentioned (and it's one of the things I tried before digging into xrandr's source to figure out why it was filtering).
It also has the same problems with aliasing, blurriness, and artifacts (the blurriness and bad hinting become more pronounced and the artifacts take a back seat)
Isn't especially mac known for having various issues with dual monitor setups? Sure the scaling works pretty well but the flicker and the idea that you can only use it with power cable are definitly deal breakers for me.
I'm impressed you'd call that "pretty much perfect and comparable (if not better) to macOS with a recent distro"
Pretty much sums up why I don't think I'll ever really be ok with a Linux DE for daily usage. If that's what your users consider comparable to macOS why bother aspiring to reach macOS's perfect (seriously, perfect, even when you mirror across a low res screen and a high res screen it lets you use the high res screen at a higher size with perfect scaling) handling of any mix of resolutions.