As of "lately" in the sense of "in the last 10 years", it was always great. Freetype always had great rendering, on part and often superior to both ClearType and OSX to my eyes.
I attribute the bad perceived performance of freetype to the lack of good and/or commercial fonts.
The default configuration in most distributions is decent, but with little tuning everything can be changed to your taste. I ran with grayscale AA since the beginning because I find the color fringing annoying.
I also used to like the bytecode hinter, but in the last years with my laptop having 120+ dpi, I find the freetype autohinter to be actually superior as it better preserves the letterform and provides sharper results even without subpixel AA.
The settings can also be tailored per-font, and apply system-wide, with the exception of some stupid QML and Electron apps.
Thanks for that detailed response. I last used Linux full-time as my main machine in 2009 or so. It has indeed been a while. Good to know that it has improved since that time.
Since I will now be switching off Mac, Linux is looking likely again. It will probably be two 27" 4K monitors.